Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 1 | :mod:`xml.etree.ElementTree` --- The ElementTree XML API |
| 2 | ======================================================== |
| 3 | |
| 4 | .. module:: xml.etree.ElementTree |
| 5 | :synopsis: Implementation of the ElementTree API. |
| 6 | .. moduleauthor:: Fredrik Lundh <fredrik@pythonware.com> |
| 7 | |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 8 | The :mod:`xml.etree.ElementTree` module implements a simple and efficient API |
| 9 | for parsing and creating XML data. |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 10 | |
Florent Xicluna | a72a98f | 2012-02-13 11:03:30 +0100 | [diff] [blame] | 11 | .. versionchanged:: 3.3 |
| 12 | This module will use a fast implementation whenever available. |
| 13 | The :mod:`xml.etree.cElementTree` module is deprecated. |
| 14 | |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 15 | Tutorial |
| 16 | -------- |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 17 | |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 18 | This is a short tutorial for using :mod:`xml.etree.ElementTree` (``ET`` in |
| 19 | short). The goal is to demonstrate some of the building blocks and basic |
| 20 | concepts of the module. |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 21 | |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 22 | XML tree and elements |
| 23 | ^^^^^^^^^^^^^^^^^^^^^ |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 24 | |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 25 | XML is an inherently hierarchical data format, and the most natural way to |
| 26 | represent it is with a tree. ``ET`` has two classes for this purpose - |
| 27 | :class:`ElementTree` represents the whole XML document as a tree, and |
| 28 | :class:`Element` represents a single node in this tree. Interactions with |
| 29 | the whole document (reading and writing to/from files) are usually done |
| 30 | on the :class:`ElementTree` level. Interactions with a single XML element |
| 31 | and its sub-elements are done on the :class:`Element` level. |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 32 | |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 33 | .. _elementtree-parsing-xml: |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 34 | |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 35 | Parsing XML |
| 36 | ^^^^^^^^^^^ |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 37 | |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 38 | We'll be using the following XML document as the sample data for this section: |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 39 | |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 40 | .. code-block:: xml |
| 41 | |
| 42 | <?xml version="1.0"?> |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 43 | <data> |
| 44 | <country name="Liechtenshtein"> |
| 45 | <rank>1</rank> |
| 46 | <year>2008</year> |
| 47 | <gdppc>141100</gdppc> |
| 48 | <neighbor name="Austria" direction="E"/> |
| 49 | <neighbor name="Switzerland" direction="W"/> |
| 50 | </country> |
| 51 | <country name="Singapore"> |
| 52 | <rank>4</rank> |
| 53 | <year>2011</year> |
| 54 | <gdppc>59900</gdppc> |
| 55 | <neighbor name="Malaysia" direction="N"/> |
| 56 | </country> |
| 57 | <country name="Panama"> |
| 58 | <rank>68</rank> |
| 59 | <year>2011</year> |
| 60 | <gdppc>13600</gdppc> |
| 61 | <neighbor name="Costa Rica" direction="W"/> |
| 62 | <neighbor name="Colombia" direction="E"/> |
| 63 | </country> |
| 64 | </data> |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 65 | |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 66 | We can import this data by reading from a file:: |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 67 | |
| 68 | import xml.etree.ElementTree as ET |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 69 | tree = ET.parse('country_data.xml') |
| 70 | root = tree.getroot() |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 71 | |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 72 | Or directly from a string:: |
| 73 | |
| 74 | root = ET.fromstring(country_data_as_string) |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 75 | |
| 76 | :func:`fromstring` parses XML from a string directly into an :class:`Element`, |
| 77 | which is the root element of the parsed tree. Other parsing functions may |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 78 | create an :class:`ElementTree`. Check the documentation to be sure. |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 79 | |
| 80 | As an :class:`Element`, ``root`` has a tag and a dictionary of attributes:: |
| 81 | |
| 82 | >>> root.tag |
| 83 | 'data' |
| 84 | >>> root.attrib |
| 85 | {} |
| 86 | |
| 87 | It also has children nodes over which we can iterate:: |
| 88 | |
| 89 | >>> for child in root: |
| 90 | ... print(child.tag, child.attrib) |
| 91 | ... |
| 92 | country {'name': 'Liechtenshtein'} |
| 93 | country {'name': 'Singapore'} |
| 94 | country {'name': 'Panama'} |
| 95 | |
| 96 | Children are nested, and we can access specific child nodes by index:: |
| 97 | |
| 98 | >>> root[0][1].text |
| 99 | '2008' |
| 100 | |
| 101 | Finding interesting elements |
| 102 | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ |
| 103 | |
| 104 | :class:`Element` has some useful methods that help iterate recursively over all |
| 105 | the sub-tree below it (its children, their children, and so on). For example, |
| 106 | :meth:`Element.iter`:: |
| 107 | |
| 108 | >>> for neighbor in root.iter('neighbor'): |
| 109 | ... print(neighbor.attrib) |
| 110 | ... |
| 111 | {'name': 'Austria', 'direction': 'E'} |
| 112 | {'name': 'Switzerland', 'direction': 'W'} |
| 113 | {'name': 'Malaysia', 'direction': 'N'} |
| 114 | {'name': 'Costa Rica', 'direction': 'W'} |
| 115 | {'name': 'Colombia', 'direction': 'E'} |
| 116 | |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 117 | :meth:`Element.findall` finds only elements with a tag which are direct |
| 118 | children of the current element. :meth:`Element.find` finds the *first* child |
| 119 | with a particular tag, and :meth:`Element.text` accesses the element's text |
| 120 | content. :meth:`Element.get` accesses the element's attributes:: |
| 121 | |
| 122 | >>> for country in root.findall('country'): |
| 123 | ... rank = country.find('rank').text |
| 124 | ... name = country.get('name') |
| 125 | ... print(name, rank) |
| 126 | ... |
| 127 | Liechtenshtein 1 |
| 128 | Singapore 4 |
| 129 | Panama 68 |
| 130 | |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 131 | More sophisticated specification of which elements to look for is possible by |
| 132 | using :ref:`XPath <elementtree-xpath>`. |
| 133 | |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 134 | Modifying an XML File |
| 135 | ^^^^^^^^^^^^^^^^^^^^^ |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 136 | |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 137 | :class:`ElementTree` provides a simple way to build XML documents and write them to files. |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 138 | The :meth:`ElementTree.write` method serves this purpose. |
| 139 | |
| 140 | Once created, an :class:`Element` object may be manipulated by directly changing |
| 141 | its fields (such as :attr:`Element.text`), adding and modifying attributes |
| 142 | (:meth:`Element.set` method), as well as adding new children (for example |
| 143 | with :meth:`Element.append`). |
| 144 | |
Eli Bendersky | 0f4e934 | 2012-08-14 07:19:33 +0300 | [diff] [blame] | 145 | Let's say we want to add one to each country's rank, and add an ``updated`` |
| 146 | attribute to the rank element:: |
| 147 | |
| 148 | >>> for rank in root.iter('rank'): |
| 149 | ... new_rank = int(rank.text) + 1 |
| 150 | ... rank.text = str(new_rank) |
| 151 | ... rank.set('updated', 'yes') |
| 152 | ... |
| 153 | ... tree.write('output.xml') |
| 154 | |
| 155 | Our XML now looks like this: |
| 156 | |
| 157 | .. code-block:: xml |
| 158 | |
| 159 | <?xml version="1.0"?> |
| 160 | <data> |
| 161 | <country name="Liechtenshtein"> |
| 162 | <rank updated="yes">2</rank> |
| 163 | <year>2008</year> |
| 164 | <gdppc>141100</gdppc> |
| 165 | <neighbor name="Austria" direction="E"/> |
| 166 | <neighbor name="Switzerland" direction="W"/> |
| 167 | </country> |
| 168 | <country name="Singapore"> |
| 169 | <rank updated="yes">5</rank> |
| 170 | <year>2011</year> |
| 171 | <gdppc>59900</gdppc> |
| 172 | <neighbor name="Malaysia" direction="N"/> |
| 173 | </country> |
| 174 | <country name="Panama"> |
| 175 | <rank updated="yes">69</rank> |
| 176 | <year>2011</year> |
| 177 | <gdppc>13600</gdppc> |
| 178 | <neighbor name="Costa Rica" direction="W"/> |
| 179 | <neighbor name="Colombia" direction="E"/> |
| 180 | </country> |
| 181 | </data> |
| 182 | |
| 183 | We can remove elements using :meth:`Element.remove`. Let's say we want to |
| 184 | remove all countries with a rank higher than 50:: |
| 185 | |
| 186 | >>> for country in root.findall('country'): |
| 187 | ... rank = int(country.find('rank').text) |
| 188 | ... if rank > 50: |
| 189 | ... root.remove(country) |
| 190 | ... |
| 191 | ... tree.write('output.xml') |
| 192 | |
| 193 | Our XML now looks like this: |
| 194 | |
| 195 | .. code-block:: xml |
| 196 | |
| 197 | <?xml version="1.0"?> |
| 198 | <data> |
| 199 | <country name="Liechtenshtein"> |
| 200 | <rank updated="yes">2</rank> |
| 201 | <year>2008</year> |
| 202 | <gdppc>141100</gdppc> |
| 203 | <neighbor name="Austria" direction="E"/> |
| 204 | <neighbor name="Switzerland" direction="W"/> |
| 205 | </country> |
| 206 | <country name="Singapore"> |
| 207 | <rank updated="yes">5</rank> |
| 208 | <year>2011</year> |
| 209 | <gdppc>59900</gdppc> |
| 210 | <neighbor name="Malaysia" direction="N"/> |
| 211 | </country> |
| 212 | </data> |
| 213 | |
| 214 | Building XML documents |
| 215 | ^^^^^^^^^^^^^^^^^^^^^^ |
| 216 | |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 217 | The :func:`SubElement` function also provides a convenient way to create new |
| 218 | sub-elements for a given element:: |
| 219 | |
| 220 | >>> a = ET.Element('a') |
| 221 | >>> b = ET.SubElement(a, 'b') |
| 222 | >>> c = ET.SubElement(a, 'c') |
| 223 | >>> d = ET.SubElement(c, 'd') |
| 224 | >>> ET.dump(a) |
| 225 | <a><b /><c><d /></c></a> |
| 226 | |
| 227 | Additional resources |
| 228 | ^^^^^^^^^^^^^^^^^^^^ |
| 229 | |
| 230 | See http://effbot.org/zone/element-index.htm for tutorials and links to other |
| 231 | docs. |
| 232 | |
| 233 | |
| 234 | .. _elementtree-xpath: |
| 235 | |
| 236 | XPath support |
| 237 | ------------- |
| 238 | |
| 239 | This module provides limited support for |
| 240 | `XPath expressions <http://www.w3.org/TR/xpath>`_ for locating elements in a |
| 241 | tree. The goal is to support a small subset of the abbreviated syntax; a full |
| 242 | XPath engine is outside the scope of the module. |
| 243 | |
| 244 | Example |
| 245 | ^^^^^^^ |
| 246 | |
| 247 | Here's an example that demonstrates some of the XPath capabilities of the |
| 248 | module. We'll be using the ``countrydata`` XML document from the |
| 249 | :ref:`Parsing XML <elementtree-parsing-xml>` section:: |
| 250 | |
| 251 | import xml.etree.ElementTree as ET |
| 252 | |
| 253 | root = ET.fromstring(countrydata) |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 254 | |
| 255 | # Top-level elements |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 256 | root.findall(".") |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 257 | |
| 258 | # All 'neighbor' grand-children of 'country' children of the top-level |
| 259 | # elements |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 260 | root.findall("./country/neighbor") |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 261 | |
| 262 | # Nodes with name='Singapore' that have a 'year' child |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 263 | root.findall(".//year/..[@name='Singapore']") |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 264 | |
| 265 | # 'year' nodes that are children of nodes with name='Singapore' |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 266 | root.findall(".//*[@name='Singapore']/year") |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 267 | |
| 268 | # All 'neighbor' nodes that are the second child of their parent |
Eli Bendersky | c1d9869 | 2012-03-30 11:44:15 +0300 | [diff] [blame] | 269 | root.findall(".//neighbor[2]") |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 270 | |
| 271 | Supported XPath syntax |
| 272 | ^^^^^^^^^^^^^^^^^^^^^^ |
| 273 | |
| 274 | +-----------------------+------------------------------------------------------+ |
| 275 | | Syntax | Meaning | |
| 276 | +=======================+======================================================+ |
| 277 | | ``tag`` | Selects all child elements with the given tag. | |
| 278 | | | For example, ``spam`` selects all child elements | |
| 279 | | | named ``spam``, ``spam/egg`` selects all | |
| 280 | | | grandchildren named ``egg`` in all children named | |
| 281 | | | ``spam``. | |
| 282 | +-----------------------+------------------------------------------------------+ |
| 283 | | ``*`` | Selects all child elements. For example, ``*/egg`` | |
| 284 | | | selects all grandchildren named ``egg``. | |
| 285 | +-----------------------+------------------------------------------------------+ |
| 286 | | ``.`` | Selects the current node. This is mostly useful | |
| 287 | | | at the beginning of the path, to indicate that it's | |
| 288 | | | a relative path. | |
| 289 | +-----------------------+------------------------------------------------------+ |
| 290 | | ``//`` | Selects all subelements, on all levels beneath the | |
Eli Bendersky | ede001a | 2012-03-27 04:57:23 +0200 | [diff] [blame] | 291 | | | current element. For example, ``.//egg`` selects | |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 292 | | | all ``egg`` elements in the entire tree. | |
| 293 | +-----------------------+------------------------------------------------------+ |
| 294 | | ``..`` | Selects the parent element. | |
| 295 | +-----------------------+------------------------------------------------------+ |
| 296 | | ``[@attrib]`` | Selects all elements that have the given attribute. | |
| 297 | +-----------------------+------------------------------------------------------+ |
| 298 | | ``[@attrib='value']`` | Selects all elements for which the given attribute | |
| 299 | | | has the given value. The value cannot contain | |
| 300 | | | quotes. | |
| 301 | +-----------------------+------------------------------------------------------+ |
| 302 | | ``[tag]`` | Selects all elements that have a child named | |
| 303 | | | ``tag``. Only immediate children are supported. | |
| 304 | +-----------------------+------------------------------------------------------+ |
| 305 | | ``[position]`` | Selects all elements that are located at the given | |
| 306 | | | position. The position can be either an integer | |
| 307 | | | (1 is the first position), the expression ``last()`` | |
| 308 | | | (for the last position), or a position relative to | |
| 309 | | | the last position (e.g. ``last()-1``). | |
| 310 | +-----------------------+------------------------------------------------------+ |
| 311 | |
| 312 | Predicates (expressions within square brackets) must be preceded by a tag |
| 313 | name, an asterisk, or another predicate. ``position`` predicates must be |
| 314 | preceded by a tag name. |
| 315 | |
| 316 | Reference |
| 317 | --------- |
| 318 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 319 | .. _elementtree-functions: |
| 320 | |
| 321 | Functions |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 322 | ^^^^^^^^^ |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 323 | |
| 324 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 325 | .. function:: Comment(text=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 326 | |
Georg Brandl | f694518 | 2008-02-01 11:56:49 +0000 | [diff] [blame] | 327 | Comment element factory. This factory function creates a special element |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 328 | that will be serialized as an XML comment by the standard serializer. The |
| 329 | comment string can be either a bytestring or a Unicode string. *text* is a |
| 330 | string containing the comment string. Returns an element instance |
Georg Brandl | f694518 | 2008-02-01 11:56:49 +0000 | [diff] [blame] | 331 | representing a comment. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 332 | |
| 333 | |
| 334 | .. function:: dump(elem) |
| 335 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 336 | Writes an element tree or element structure to sys.stdout. This function |
| 337 | should be used for debugging only. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 338 | |
| 339 | The exact output format is implementation dependent. In this version, it's |
| 340 | written as an ordinary XML file. |
| 341 | |
| 342 | *elem* is an element tree or an individual element. |
| 343 | |
| 344 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 345 | .. function:: fromstring(text) |
| 346 | |
Florent Xicluna | dddd5e9 | 2010-03-14 01:28:07 +0000 | [diff] [blame] | 347 | Parses an XML section from a string constant. Same as :func:`XML`. *text* |
| 348 | is a string containing XML data. Returns an :class:`Element` instance. |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 349 | |
| 350 | |
| 351 | .. function:: fromstringlist(sequence, parser=None) |
| 352 | |
| 353 | Parses an XML document from a sequence of string fragments. *sequence* is a |
| 354 | list or other sequence containing XML data fragments. *parser* is an |
| 355 | optional parser instance. If not given, the standard :class:`XMLParser` |
| 356 | parser is used. Returns an :class:`Element` instance. |
| 357 | |
Ezio Melotti | f8754a6 | 2010-03-21 07:16:43 +0000 | [diff] [blame] | 358 | .. versionadded:: 3.2 |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 359 | |
| 360 | |
| 361 | .. function:: iselement(element) |
| 362 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 363 | Checks if an object appears to be a valid element object. *element* is an |
| 364 | element instance. Returns a true value if this is an element object. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 365 | |
| 366 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 367 | .. function:: iterparse(source, events=None, parser=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 368 | |
| 369 | Parses an XML section into an element tree incrementally, and reports what's |
Eli Bendersky | 604c4ff | 2012-03-16 08:41:30 +0200 | [diff] [blame] | 370 | going on to the user. *source* is a filename or :term:`file object` |
| 371 | containing XML data. *events* is a list of events to report back. The |
| 372 | supported events are the strings ``"start"``, ``"end"``, ``"start-ns"`` |
| 373 | and ``"end-ns"`` (the "ns" events are used to get detailed namespace |
| 374 | information). If *events* is omitted, only ``"end"`` events are reported. |
| 375 | *parser* is an optional parser instance. If not given, the standard |
| 376 | :class:`XMLParser` parser is used. Returns an :term:`iterator` providing |
| 377 | ``(event, elem)`` pairs. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 378 | |
Benjamin Peterson | 75edad0 | 2009-01-01 15:05:06 +0000 | [diff] [blame] | 379 | .. note:: |
| 380 | |
| 381 | :func:`iterparse` only guarantees that it has seen the ">" |
| 382 | character of a starting tag when it emits a "start" event, so the |
| 383 | attributes are defined, but the contents of the text and tail attributes |
| 384 | are undefined at that point. The same applies to the element children; |
| 385 | they may or may not be present. |
| 386 | |
| 387 | If you need a fully populated element, look for "end" events instead. |
| 388 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 389 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 390 | .. function:: parse(source, parser=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 391 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 392 | Parses an XML section into an element tree. *source* is a filename or file |
| 393 | object containing XML data. *parser* is an optional parser instance. If |
| 394 | not given, the standard :class:`XMLParser` parser is used. Returns an |
| 395 | :class:`ElementTree` instance. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 396 | |
| 397 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 398 | .. function:: ProcessingInstruction(target, text=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 399 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 400 | PI element factory. This factory function creates a special element that |
| 401 | will be serialized as an XML processing instruction. *target* is a string |
| 402 | containing the PI target. *text* is a string containing the PI contents, if |
| 403 | given. Returns an element instance, representing a processing instruction. |
| 404 | |
| 405 | |
| 406 | .. function:: register_namespace(prefix, uri) |
| 407 | |
| 408 | Registers a namespace prefix. The registry is global, and any existing |
| 409 | mapping for either the given prefix or the namespace URI will be removed. |
| 410 | *prefix* is a namespace prefix. *uri* is a namespace uri. Tags and |
| 411 | attributes in this namespace will be serialized with the given prefix, if at |
| 412 | all possible. |
| 413 | |
Ezio Melotti | f8754a6 | 2010-03-21 07:16:43 +0000 | [diff] [blame] | 414 | .. versionadded:: 3.2 |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 415 | |
| 416 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 417 | .. function:: SubElement(parent, tag, attrib={}, **extra) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 418 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 419 | Subelement factory. This function creates an element instance, and appends |
| 420 | it to an existing element. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 421 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 422 | The element name, attribute names, and attribute values can be either |
| 423 | bytestrings or Unicode strings. *parent* is the parent element. *tag* is |
| 424 | the subelement name. *attrib* is an optional dictionary, containing element |
| 425 | attributes. *extra* contains additional attributes, given as keyword |
| 426 | arguments. Returns an element instance. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 427 | |
| 428 | |
Florent Xicluna | c17f172 | 2010-08-08 19:48:29 +0000 | [diff] [blame] | 429 | .. function:: tostring(element, encoding="us-ascii", method="xml") |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 430 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 431 | Generates a string representation of an XML element, including all |
Florent Xicluna | dddd5e9 | 2010-03-14 01:28:07 +0000 | [diff] [blame] | 432 | subelements. *element* is an :class:`Element` instance. *encoding* [1]_ is |
Florent Xicluna | c17f172 | 2010-08-08 19:48:29 +0000 | [diff] [blame] | 433 | the output encoding (default is US-ASCII). Use ``encoding="unicode"`` to |
| 434 | generate a Unicode string. *method* is either ``"xml"``, |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 435 | ``"html"`` or ``"text"`` (default is ``"xml"``). Returns an (optionally) |
| 436 | encoded string containing the XML data. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 437 | |
| 438 | |
Florent Xicluna | c17f172 | 2010-08-08 19:48:29 +0000 | [diff] [blame] | 439 | .. function:: tostringlist(element, encoding="us-ascii", method="xml") |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 440 | |
| 441 | Generates a string representation of an XML element, including all |
Florent Xicluna | dddd5e9 | 2010-03-14 01:28:07 +0000 | [diff] [blame] | 442 | subelements. *element* is an :class:`Element` instance. *encoding* [1]_ is |
Florent Xicluna | c17f172 | 2010-08-08 19:48:29 +0000 | [diff] [blame] | 443 | the output encoding (default is US-ASCII). Use ``encoding="unicode"`` to |
| 444 | generate a Unicode string. *method* is either ``"xml"``, |
Florent Xicluna | dddd5e9 | 2010-03-14 01:28:07 +0000 | [diff] [blame] | 445 | ``"html"`` or ``"text"`` (default is ``"xml"``). Returns a list of |
| 446 | (optionally) encoded strings containing the XML data. It does not guarantee |
| 447 | any specific sequence, except that ``"".join(tostringlist(element)) == |
| 448 | tostring(element)``. |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 449 | |
Ezio Melotti | f8754a6 | 2010-03-21 07:16:43 +0000 | [diff] [blame] | 450 | .. versionadded:: 3.2 |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 451 | |
| 452 | |
| 453 | .. function:: XML(text, parser=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 454 | |
| 455 | Parses an XML section from a string constant. This function can be used to |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 456 | embed "XML literals" in Python code. *text* is a string containing XML |
| 457 | data. *parser* is an optional parser instance. If not given, the standard |
| 458 | :class:`XMLParser` parser is used. Returns an :class:`Element` instance. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 459 | |
| 460 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 461 | .. function:: XMLID(text, parser=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 462 | |
| 463 | Parses an XML section from a string constant, and also returns a dictionary |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 464 | which maps from element id:s to elements. *text* is a string containing XML |
| 465 | data. *parser* is an optional parser instance. If not given, the standard |
| 466 | :class:`XMLParser` parser is used. Returns a tuple containing an |
| 467 | :class:`Element` instance and a dictionary. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 468 | |
| 469 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 470 | .. _elementtree-element-objects: |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 471 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 472 | Element Objects |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 473 | ^^^^^^^^^^^^^^^ |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 474 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 475 | .. class:: Element(tag, attrib={}, **extra) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 476 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 477 | Element class. This class defines the Element interface, and provides a |
| 478 | reference implementation of this interface. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 479 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 480 | The element name, attribute names, and attribute values can be either |
| 481 | bytestrings or Unicode strings. *tag* is the element name. *attrib* is |
| 482 | an optional dictionary, containing element attributes. *extra* contains |
| 483 | additional attributes, given as keyword arguments. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 484 | |
| 485 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 486 | .. attribute:: tag |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 487 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 488 | A string identifying what kind of data this element represents (the |
| 489 | element type, in other words). |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 490 | |
| 491 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 492 | .. attribute:: text |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 493 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 494 | The *text* attribute can be used to hold additional data associated with |
| 495 | the element. As the name implies this attribute is usually a string but |
| 496 | may be any application-specific object. If the element is created from |
| 497 | an XML file the attribute will contain any text found between the element |
| 498 | tags. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 499 | |
| 500 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 501 | .. attribute:: tail |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 502 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 503 | The *tail* attribute can be used to hold additional data associated with |
| 504 | the element. This attribute is usually a string but may be any |
| 505 | application-specific object. If the element is created from an XML file |
| 506 | the attribute will contain any text found after the element's end tag and |
| 507 | before the next tag. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 508 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 509 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 510 | .. attribute:: attrib |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 511 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 512 | A dictionary containing the element's attributes. Note that while the |
| 513 | *attrib* value is always a real mutable Python dictionary, an ElementTree |
| 514 | implementation may choose to use another internal representation, and |
| 515 | create the dictionary only if someone asks for it. To take advantage of |
| 516 | such implementations, use the dictionary methods below whenever possible. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 517 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 518 | The following dictionary-like methods work on the element attributes. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 519 | |
| 520 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 521 | .. method:: clear() |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 522 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 523 | Resets an element. This function removes all subelements, clears all |
| 524 | attributes, and sets the text and tail attributes to None. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 525 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 526 | |
| 527 | .. method:: get(key, default=None) |
| 528 | |
| 529 | Gets the element attribute named *key*. |
| 530 | |
| 531 | Returns the attribute value, or *default* if the attribute was not found. |
| 532 | |
| 533 | |
| 534 | .. method:: items() |
| 535 | |
| 536 | Returns the element attributes as a sequence of (name, value) pairs. The |
| 537 | attributes are returned in an arbitrary order. |
| 538 | |
| 539 | |
| 540 | .. method:: keys() |
| 541 | |
| 542 | Returns the elements attribute names as a list. The names are returned |
| 543 | in an arbitrary order. |
| 544 | |
| 545 | |
| 546 | .. method:: set(key, value) |
| 547 | |
| 548 | Set the attribute *key* on the element to *value*. |
| 549 | |
| 550 | The following methods work on the element's children (subelements). |
| 551 | |
| 552 | |
| 553 | .. method:: append(subelement) |
| 554 | |
Eli Bendersky | 396e8fc | 2012-03-23 14:24:20 +0200 | [diff] [blame] | 555 | Adds the element *subelement* to the end of this element's internal list |
| 556 | of subelements. Raises :exc:`TypeError` if *subelement* is not an |
| 557 | :class:`Element`. |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 558 | |
| 559 | |
| 560 | .. method:: extend(subelements) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 561 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 562 | Appends *subelements* from a sequence object with zero or more elements. |
Eli Bendersky | 396e8fc | 2012-03-23 14:24:20 +0200 | [diff] [blame] | 563 | Raises :exc:`TypeError` if a subelement is not an :class:`Element`. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 564 | |
Ezio Melotti | f8754a6 | 2010-03-21 07:16:43 +0000 | [diff] [blame] | 565 | .. versionadded:: 3.2 |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 566 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 567 | |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 568 | .. method:: find(match, namespaces=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 569 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 570 | Finds the first subelement matching *match*. *match* may be a tag name |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 571 | or a :ref:`path <elementtree-xpath>`. Returns an element instance |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 572 | or ``None``. *namespaces* is an optional mapping from namespace prefix |
| 573 | to full name. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 574 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 575 | |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 576 | .. method:: findall(match, namespaces=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 577 | |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 578 | Finds all matching subelements, by tag name or |
| 579 | :ref:`path <elementtree-xpath>`. Returns a list containing all matching |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 580 | elements in document order. *namespaces* is an optional mapping from |
| 581 | namespace prefix to full name. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 582 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 583 | |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 584 | .. method:: findtext(match, default=None, namespaces=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 585 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 586 | Finds text for the first subelement matching *match*. *match* may be |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 587 | a tag name or a :ref:`path <elementtree-xpath>`. Returns the text content |
| 588 | of the first matching element, or *default* if no element was found. |
| 589 | Note that if the matching element has no text content an empty string |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 590 | is returned. *namespaces* is an optional mapping from namespace prefix |
| 591 | to full name. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 592 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 593 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 594 | .. method:: getchildren() |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 595 | |
Georg Brandl | 67b21b7 | 2010-08-17 15:07:14 +0000 | [diff] [blame] | 596 | .. deprecated:: 3.2 |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 597 | Use ``list(elem)`` or iteration. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 598 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 599 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 600 | .. method:: getiterator(tag=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 601 | |
Georg Brandl | 67b21b7 | 2010-08-17 15:07:14 +0000 | [diff] [blame] | 602 | .. deprecated:: 3.2 |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 603 | Use method :meth:`Element.iter` instead. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 604 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 605 | |
Eli Bendersky | 396e8fc | 2012-03-23 14:24:20 +0200 | [diff] [blame] | 606 | .. method:: insert(index, subelement) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 607 | |
Eli Bendersky | 396e8fc | 2012-03-23 14:24:20 +0200 | [diff] [blame] | 608 | Inserts *subelement* at the given position in this element. Raises |
| 609 | :exc:`TypeError` if *subelement* is not an :class:`Element`. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 610 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 611 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 612 | .. method:: iter(tag=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 613 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 614 | Creates a tree :term:`iterator` with the current element as the root. |
| 615 | The iterator iterates over this element and all elements below it, in |
| 616 | document (depth first) order. If *tag* is not ``None`` or ``'*'``, only |
| 617 | elements whose tag equals *tag* are returned from the iterator. If the |
| 618 | tree structure is modified during iteration, the result is undefined. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 619 | |
Ezio Melotti | 138fc89 | 2011-10-10 00:02:03 +0300 | [diff] [blame] | 620 | .. versionadded:: 3.2 |
| 621 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 622 | |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 623 | .. method:: iterfind(match, namespaces=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 624 | |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 625 | Finds all matching subelements, by tag name or |
| 626 | :ref:`path <elementtree-xpath>`. Returns an iterable yielding all |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 627 | matching elements in document order. *namespaces* is an optional mapping |
| 628 | from namespace prefix to full name. |
| 629 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 630 | |
Ezio Melotti | f8754a6 | 2010-03-21 07:16:43 +0000 | [diff] [blame] | 631 | .. versionadded:: 3.2 |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 632 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 633 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 634 | .. method:: itertext() |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 635 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 636 | Creates a text iterator. The iterator loops over this element and all |
| 637 | subelements, in document order, and returns all inner text. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 638 | |
Ezio Melotti | f8754a6 | 2010-03-21 07:16:43 +0000 | [diff] [blame] | 639 | .. versionadded:: 3.2 |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 640 | |
| 641 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 642 | .. method:: makeelement(tag, attrib) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 643 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 644 | Creates a new element object of the same type as this element. Do not |
| 645 | call this method, use the :func:`SubElement` factory function instead. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 646 | |
| 647 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 648 | .. method:: remove(subelement) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 649 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 650 | Removes *subelement* from the element. Unlike the find\* methods this |
| 651 | method compares elements based on the instance identity, not on tag value |
| 652 | or contents. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 653 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 654 | :class:`Element` objects also support the following sequence type methods |
| 655 | for working with subelements: :meth:`__delitem__`, :meth:`__getitem__`, |
| 656 | :meth:`__setitem__`, :meth:`__len__`. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 657 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 658 | Caution: Elements with no subelements will test as ``False``. This behavior |
| 659 | will change in future versions. Use specific ``len(elem)`` or ``elem is |
| 660 | None`` test instead. :: |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 661 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 662 | element = root.find('foo') |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 663 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 664 | if not element: # careful! |
| 665 | print("element not found, or element has no subelements") |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 666 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 667 | if element is None: |
| 668 | print("element not found") |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 669 | |
| 670 | |
| 671 | .. _elementtree-elementtree-objects: |
| 672 | |
| 673 | ElementTree Objects |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 674 | ^^^^^^^^^^^^^^^^^^^ |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 675 | |
| 676 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 677 | .. class:: ElementTree(element=None, file=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 678 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 679 | ElementTree wrapper class. This class represents an entire element |
| 680 | hierarchy, and adds some extra support for serialization to and from |
| 681 | standard XML. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 682 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 683 | *element* is the root element. The tree is initialized with the contents |
| 684 | of the XML *file* if given. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 685 | |
| 686 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 687 | .. method:: _setroot(element) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 688 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 689 | Replaces the root element for this tree. This discards the current |
| 690 | contents of the tree, and replaces it with the given element. Use with |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 691 | care. *element* is an element instance. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 692 | |
| 693 | |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 694 | .. method:: find(match, namespaces=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 695 | |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 696 | Same as :meth:`Element.find`, starting at the root of the tree. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 697 | |
| 698 | |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 699 | .. method:: findall(match, namespaces=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 700 | |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 701 | Same as :meth:`Element.findall`, starting at the root of the tree. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 702 | |
| 703 | |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 704 | .. method:: findtext(match, default=None, namespaces=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 705 | |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 706 | Same as :meth:`Element.findtext`, starting at the root of the tree. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 707 | |
| 708 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 709 | .. method:: getiterator(tag=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 710 | |
Georg Brandl | 67b21b7 | 2010-08-17 15:07:14 +0000 | [diff] [blame] | 711 | .. deprecated:: 3.2 |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 712 | Use method :meth:`ElementTree.iter` instead. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 713 | |
| 714 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 715 | .. method:: getroot() |
Florent Xicluna | c17f172 | 2010-08-08 19:48:29 +0000 | [diff] [blame] | 716 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 717 | Returns the root element for this tree. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 718 | |
| 719 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 720 | .. method:: iter(tag=None) |
| 721 | |
| 722 | Creates and returns a tree iterator for the root element. The iterator |
| 723 | loops over all elements in this tree, in section order. *tag* is the tag |
| 724 | to look for (default is to return all elements) |
| 725 | |
| 726 | |
Eli Bendersky | 737b173 | 2012-05-29 06:02:56 +0300 | [diff] [blame] | 727 | .. method:: iterfind(match, namespaces=None) |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 728 | |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 729 | Same as :meth:`Element.iterfind`, starting at the root of the tree. |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 730 | |
Ezio Melotti | f8754a6 | 2010-03-21 07:16:43 +0000 | [diff] [blame] | 731 | .. versionadded:: 3.2 |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 732 | |
| 733 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 734 | .. method:: parse(source, parser=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 735 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 736 | Loads an external XML section into this element tree. *source* is a file |
Antoine Pitrou | 11cb961 | 2010-09-15 11:11:28 +0000 | [diff] [blame] | 737 | name or :term:`file object`. *parser* is an optional parser instance. |
Eli Bendersky | 52467b1 | 2012-06-01 07:13:08 +0300 | [diff] [blame] | 738 | If not given, the standard :class:`XMLParser` parser is used. Returns the |
| 739 | section root element. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 740 | |
| 741 | |
Eli Bendersky | f96cf91 | 2012-07-15 06:19:44 +0300 | [diff] [blame] | 742 | .. method:: write(file, encoding="us-ascii", xml_declaration=None, \ |
| 743 | method="xml") |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 744 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 745 | Writes the element tree to a file, as XML. *file* is a file name, or a |
Eli Bendersky | f96cf91 | 2012-07-15 06:19:44 +0300 | [diff] [blame] | 746 | :term:`file object` opened for writing. *encoding* [1]_ is the output |
| 747 | encoding (default is US-ASCII). |
| 748 | *xml_declaration* controls if an XML declaration should be added to the |
| 749 | file. Use ``False`` for never, ``True`` for always, ``None`` |
| 750 | for only if not US-ASCII or UTF-8 or Unicode (default is ``None``). |
| 751 | *method* is either ``"xml"``, ``"html"`` or ``"text"`` (default is |
| 752 | ``"xml"``). |
| 753 | |
| 754 | The output is either a string (:class:`str`) or binary (:class:`bytes`). |
| 755 | This is controlled by the *encoding* argument. If *encoding* is |
| 756 | ``"unicode"``, the output is a string; otherwise, it's binary. Note that |
| 757 | this may conflict with the type of *file* if it's an open |
| 758 | :term:`file object`; make sure you do not try to write a string to a |
| 759 | binary stream and vice versa. |
| 760 | |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 761 | |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 762 | This is the XML file that is going to be manipulated:: |
| 763 | |
| 764 | <html> |
| 765 | <head> |
| 766 | <title>Example page</title> |
| 767 | </head> |
| 768 | <body> |
Georg Brandl | 48310cd | 2009-01-03 21:18:54 +0000 | [diff] [blame] | 769 | <p>Moved to <a href="http://example.org/">example.org</a> |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 770 | or <a href="http://example.com/">example.com</a>.</p> |
| 771 | </body> |
| 772 | </html> |
| 773 | |
| 774 | Example of changing the attribute "target" of every link in first paragraph:: |
| 775 | |
| 776 | >>> from xml.etree.ElementTree import ElementTree |
| 777 | >>> tree = ElementTree() |
| 778 | >>> tree.parse("index.xhtml") |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 779 | <Element 'html' at 0xb77e6fac> |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 780 | >>> p = tree.find("body/p") # Finds first occurrence of tag p in body |
| 781 | >>> p |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 782 | <Element 'p' at 0xb77ec26c> |
| 783 | >>> links = list(p.iter("a")) # Returns list of all links |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 784 | >>> links |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 785 | [<Element 'a' at 0xb77ec2ac>, <Element 'a' at 0xb77ec1cc>] |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 786 | >>> for i in links: # Iterates through all found links |
| 787 | ... i.attrib["target"] = "blank" |
| 788 | >>> tree.write("output.xhtml") |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 789 | |
| 790 | .. _elementtree-qname-objects: |
| 791 | |
| 792 | QName Objects |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 793 | ^^^^^^^^^^^^^ |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 794 | |
| 795 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 796 | .. class:: QName(text_or_uri, tag=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 797 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 798 | QName wrapper. This can be used to wrap a QName attribute value, in order |
| 799 | to get proper namespace handling on output. *text_or_uri* is a string |
| 800 | containing the QName value, in the form {uri}local, or, if the tag argument |
| 801 | is given, the URI part of a QName. If *tag* is given, the first argument is |
| 802 | interpreted as an URI, and this argument is interpreted as a local name. |
| 803 | :class:`QName` instances are opaque. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 804 | |
| 805 | |
| 806 | .. _elementtree-treebuilder-objects: |
| 807 | |
| 808 | TreeBuilder Objects |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 809 | ^^^^^^^^^^^^^^^^^^^ |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 810 | |
| 811 | |
Georg Brandl | 7f01a13 | 2009-09-16 15:58:14 +0000 | [diff] [blame] | 812 | .. class:: TreeBuilder(element_factory=None) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 813 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 814 | Generic element structure builder. This builder converts a sequence of |
| 815 | start, data, and end method calls to a well-formed element structure. You |
| 816 | can use this class to build an element structure using a custom XML parser, |
Eli Bendersky | 48d358b | 2012-05-30 17:57:50 +0300 | [diff] [blame] | 817 | or a parser for some other XML-like format. *element_factory*, when given, |
| 818 | must be a callable accepting two positional arguments: a tag and |
| 819 | a dict of attributes. It is expected to return a new element instance. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 820 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 821 | .. method:: close() |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 822 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 823 | Flushes the builder buffers, and returns the toplevel document |
| 824 | element. Returns an :class:`Element` instance. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 825 | |
| 826 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 827 | .. method:: data(data) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 828 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 829 | Adds text to the current element. *data* is a string. This should be |
| 830 | either a bytestring, or a Unicode string. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 831 | |
| 832 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 833 | .. method:: end(tag) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 834 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 835 | Closes the current element. *tag* is the element name. Returns the |
| 836 | closed element. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 837 | |
| 838 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 839 | .. method:: start(tag, attrs) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 840 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 841 | Opens a new element. *tag* is the element name. *attrs* is a dictionary |
| 842 | containing element attributes. Returns the opened element. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 843 | |
| 844 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 845 | In addition, a custom :class:`TreeBuilder` object can provide the |
| 846 | following method: |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 847 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 848 | .. method:: doctype(name, pubid, system) |
| 849 | |
| 850 | Handles a doctype declaration. *name* is the doctype name. *pubid* is |
| 851 | the public identifier. *system* is the system identifier. This method |
| 852 | does not exist on the default :class:`TreeBuilder` class. |
| 853 | |
Ezio Melotti | f8754a6 | 2010-03-21 07:16:43 +0000 | [diff] [blame] | 854 | .. versionadded:: 3.2 |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 855 | |
| 856 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 857 | .. _elementtree-xmlparser-objects: |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 858 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 859 | XMLParser Objects |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 860 | ^^^^^^^^^^^^^^^^^ |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 861 | |
| 862 | |
| 863 | .. class:: XMLParser(html=0, target=None, encoding=None) |
| 864 | |
| 865 | :class:`Element` structure builder for XML source data, based on the expat |
| 866 | parser. *html* are predefined HTML entities. This flag is not supported by |
| 867 | the current implementation. *target* is the target object. If omitted, the |
Eli Bendersky | 1bf2394 | 2012-06-01 07:15:00 +0300 | [diff] [blame] | 868 | builder uses an instance of the standard :class:`TreeBuilder` class. |
Eli Bendersky | 52467b1 | 2012-06-01 07:13:08 +0300 | [diff] [blame] | 869 | *encoding* [1]_ is optional. If given, the value overrides the encoding |
| 870 | specified in the XML file. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 871 | |
| 872 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 873 | .. method:: close() |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 874 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 875 | Finishes feeding data to the parser. Returns an element structure. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 876 | |
| 877 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 878 | .. method:: doctype(name, pubid, system) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 879 | |
Georg Brandl | 67b21b7 | 2010-08-17 15:07:14 +0000 | [diff] [blame] | 880 | .. deprecated:: 3.2 |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 881 | Define the :meth:`TreeBuilder.doctype` method on a custom TreeBuilder |
| 882 | target. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 883 | |
| 884 | |
Benjamin Peterson | e41251e | 2008-04-25 01:59:09 +0000 | [diff] [blame] | 885 | .. method:: feed(data) |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 886 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 887 | Feeds data to the parser. *data* is encoded data. |
Georg Brandl | 116aa62 | 2007-08-15 14:28:22 +0000 | [diff] [blame] | 888 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 889 | :meth:`XMLParser.feed` calls *target*\'s :meth:`start` method |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 890 | for each opening tag, its :meth:`end` method for each closing tag, |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 891 | and data is processed by method :meth:`data`. :meth:`XMLParser.close` |
Georg Brandl | 48310cd | 2009-01-03 21:18:54 +0000 | [diff] [blame] | 892 | calls *target*\'s method :meth:`close`. |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 893 | :class:`XMLParser` can be used not only for building a tree structure. |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 894 | This is an example of counting the maximum depth of an XML file:: |
| 895 | |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 896 | >>> from xml.etree.ElementTree import XMLParser |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 897 | >>> class MaxDepth: # The target object of the parser |
| 898 | ... maxDepth = 0 |
| 899 | ... depth = 0 |
| 900 | ... def start(self, tag, attrib): # Called for each opening tag. |
Georg Brandl | 48310cd | 2009-01-03 21:18:54 +0000 | [diff] [blame] | 901 | ... self.depth += 1 |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 902 | ... if self.depth > self.maxDepth: |
| 903 | ... self.maxDepth = self.depth |
| 904 | ... def end(self, tag): # Called for each closing tag. |
| 905 | ... self.depth -= 1 |
Georg Brandl | 48310cd | 2009-01-03 21:18:54 +0000 | [diff] [blame] | 906 | ... def data(self, data): |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 907 | ... pass # We do not need to do anything with data. |
| 908 | ... def close(self): # Called when all data has been parsed. |
| 909 | ... return self.maxDepth |
Georg Brandl | 48310cd | 2009-01-03 21:18:54 +0000 | [diff] [blame] | 910 | ... |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 911 | >>> target = MaxDepth() |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 912 | >>> parser = XMLParser(target=target) |
Christian Heimes | d8654cf | 2007-12-02 15:22:16 +0000 | [diff] [blame] | 913 | >>> exampleXml = """ |
| 914 | ... <a> |
| 915 | ... <b> |
| 916 | ... </b> |
| 917 | ... <b> |
| 918 | ... <c> |
| 919 | ... <d> |
| 920 | ... </d> |
| 921 | ... </c> |
| 922 | ... </b> |
| 923 | ... </a>""" |
| 924 | >>> parser.feed(exampleXml) |
| 925 | >>> parser.close() |
| 926 | 4 |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 927 | |
Eli Bendersky | 5b77d81 | 2012-03-16 08:20:05 +0200 | [diff] [blame] | 928 | Exceptions |
Eli Bendersky | 3a4875e | 2012-03-26 20:43:32 +0200 | [diff] [blame] | 929 | ^^^^^^^^^^ |
Eli Bendersky | 5b77d81 | 2012-03-16 08:20:05 +0200 | [diff] [blame] | 930 | |
| 931 | .. class:: ParseError |
| 932 | |
| 933 | XML parse error, raised by the various parsing methods in this module when |
| 934 | parsing fails. The string representation of an instance of this exception |
| 935 | will contain a user-friendly error message. In addition, it will have |
| 936 | the following attributes available: |
| 937 | |
| 938 | .. attribute:: code |
| 939 | |
| 940 | A numeric error code from the expat parser. See the documentation of |
| 941 | :mod:`xml.parsers.expat` for the list of error codes and their meanings. |
| 942 | |
| 943 | .. attribute:: position |
| 944 | |
| 945 | A tuple of *line*, *column* numbers, specifying where the error occurred. |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 946 | |
| 947 | .. rubric:: Footnotes |
| 948 | |
| 949 | .. [#] The encoding string included in XML output should conform to the |
Florent Xicluna | f15351d | 2010-03-13 23:24:31 +0000 | [diff] [blame] | 950 | appropriate standards. For example, "UTF-8" is valid, but "UTF8" is |
| 951 | not. See http://www.w3.org/TR/2006/REC-xml11-20060816/#NT-EncodingDecl |
Benjamin Peterson | ad3d5c2 | 2009-02-26 03:38:59 +0000 | [diff] [blame] | 952 | and http://www.iana.org/assignments/character-sets. |