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| 14 | <title>Validation & DTDs</title> |
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Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 16 | <body bgcolor="#8b7765" text="#000000" link="#000000" vlink="#000000"> |
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Daniel Veillard | 8f40f1e | 2002-08-28 21:18:45 +0000 | [diff] [blame] | 19 | <a href="http://www.gnome.org/"><img src="gnome2.png" alt="Gnome2 Logo"></a><a href="http://www.w3.org/Status"><img src="w3c.png" alt="W3C Logo"></a><a href="http://www.redhat.com/"><img src="redhat.gif" alt="Red Hat Logo"></a><div align="left"><a href="http://xmlsoft.org/"><img src="Libxml2-Logo-180x168.gif" alt="Made with Libxml2 Logo"></a></div> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 20 | </td> |
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| 22 | <h1>The XML C library for Gnome</h1> |
| 23 | <h2>Validation & DTDs</h2> |
| 24 | </td></tr></table></td></tr></table></td> |
| 25 | </tr></table> |
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| 29 | <tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Main Menu</b></center></td></tr> |
Daniel Veillard | 8acca11 | 2002-01-21 09:52:27 +0000 | [diff] [blame] | 30 | <tr><td bgcolor="#fffacd"><ul> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 31 | <li><a href="index.html">Home</a></li> |
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Daniel Veillard | 7b602b4 | 2002-01-08 13:26:00 +0000 | [diff] [blame] | 39 | <li><a href="XMLinfo.html">XML</a></li> |
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Daniel Veillard | 6dbcaf8 | 2002-02-20 14:37:47 +0000 | [diff] [blame] | 41 | <li><a href="python.html">Python and bindings</a></li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 42 | <li><a href="architecture.html">libxml architecture</a></li> |
| 43 | <li><a href="tree.html">The tree output</a></li> |
| 44 | <li><a href="interface.html">The SAX interface</a></li> |
| 45 | <li><a href="xmldtd.html">Validation & DTDs</a></li> |
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| 48 | <li><a href="xmlio.html">I/O Interfaces</a></li> |
| 49 | <li><a href="catalog.html">Catalog support</a></li> |
| 50 | <li><a href="library.html">The parser interfaces</a></li> |
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| 52 | <li><a href="namespaces.html">Namespaces</a></li> |
| 53 | <li><a href="upgrade.html">Upgrading 1.x code</a></li> |
Daniel Veillard | 52dcab3 | 2001-10-30 12:51:17 +0000 | [diff] [blame] | 54 | <li><a href="threads.html">Thread safety</a></li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 55 | <li><a href="DOM.html">DOM Principles</a></li> |
| 56 | <li><a href="example.html">A real example</a></li> |
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Daniel Veillard | fc59c09 | 2002-06-05 14:48:26 +0000 | [diff] [blame] | 58 | <li><a href="tutorial/index.html">Tutorial</a></li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 59 | <li> |
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Daniel Veillard | 3bf65be | 2002-01-23 12:36:34 +0000 | [diff] [blame] | 65 | <tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>API Indexes</b></center></td></tr> |
Daniel Veillard | 5ede35e | 2002-10-01 11:37:35 +0000 | [diff] [blame] | 66 | <tr><td bgcolor="#fffacd"> |
Daniel Veillard | 595978c | 2002-10-09 18:46:35 +0000 | [diff] [blame] | 67 | <form action="search.php" enctype="application/x-www-form-urlencoded" method="GET"> |
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| 70 | <ul> |
Daniel Veillard | f859256 | 2002-01-23 17:58:17 +0000 | [diff] [blame] | 71 | <li><a href="APIchunk0.html">Alphabetic</a></li> |
Daniel Veillard | 3bf65be | 2002-01-23 12:36:34 +0000 | [diff] [blame] | 72 | <li><a href="APIconstructors.html">Constructors</a></li> |
| 73 | <li><a href="APIfunctions.html">Functions/Types</a></li> |
| 74 | <li><a href="APIfiles.html">Modules</a></li> |
| 75 | <li><a href="APIsymbols.html">Symbols</a></li> |
Daniel Veillard | 5ede35e | 2002-10-01 11:37:35 +0000 | [diff] [blame] | 76 | </ul> |
| 77 | </td></tr> |
Daniel Veillard | 3bf65be | 2002-01-23 12:36:34 +0000 | [diff] [blame] | 78 | </table> |
| 79 | <table width="100%" border="0" cellspacing="1" cellpadding="3"> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 80 | <tr><td colspan="1" bgcolor="#eecfa1" align="center"><center><b>Related links</b></center></td></tr> |
Daniel Veillard | 8acca11 | 2002-01-21 09:52:27 +0000 | [diff] [blame] | 81 | <tr><td bgcolor="#fffacd"><ul> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 82 | <li><a href="http://mail.gnome.org/archives/xml/">Mail archive</a></li> |
| 83 | <li><a href="http://xmlsoft.org/XSLT/">XSLT libxslt</a></li> |
Daniel Veillard | 4a85920 | 2002-01-08 11:49:22 +0000 | [diff] [blame] | 84 | <li><a href="http://phd.cs.unibo.it/gdome2/">DOM gdome2</a></li> |
Daniel Veillard | 2d347fa | 2002-03-17 10:34:11 +0000 | [diff] [blame] | 85 | <li><a href="http://www.aleksey.com/xmlsec/">XML-DSig xmlsec</a></li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 86 | <li><a href="ftp://xmlsoft.org/">FTP</a></li> |
| 87 | <li><a href="http://www.fh-frankfurt.de/~igor/projects/libxml/">Windows binaries</a></li> |
Daniel Veillard | db9dfd9 | 2001-11-26 17:25:02 +0000 | [diff] [blame] | 88 | <li><a href="http://garypennington.net/libxml2/">Solaris binaries</a></li> |
Daniel Veillard | cb7543b | 2002-09-09 10:54:06 +0000 | [diff] [blame] | 89 | <li><a href="http://www.zveno.com/open_source/libxml2xslt.html">MacOsX binaries</a></li> |
Daniel Veillard | e6d8e20 | 2002-05-02 06:11:10 +0000 | [diff] [blame] | 90 | <li><a href="http://sourceforge.net/projects/libxml2-pas/">Pascal bindings</a></li> |
Daniel Veillard | 2d347fa | 2002-03-17 10:34:11 +0000 | [diff] [blame] | 91 | <li><a href="http://bugzilla.gnome.org/buglist.cgi?product=libxml&product=libxml2">Bug Tracker</a></li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 92 | </ul></td></tr> |
| 93 | </table> |
| 94 | </td></tr></table></td> |
| 95 | <td valign="top" bgcolor="#8b7765"><table border="0" cellspacing="0" cellpadding="1" width="100%"><tr><td><table border="0" cellspacing="0" cellpadding="1" width="100%" bgcolor="#000000"><tr><td><table border="0" cellpadding="3" cellspacing="1" width="100%"><tr><td bgcolor="#fffacd"> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 96 | <p>Table of Content:</p> |
| 97 | <ol> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 98 | <li><a href="#General5">General overview</a></li> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 99 | <li><a href="#definition">The definition</a></li> |
| 100 | <li> |
| 101 | <a href="#Simple">Simple rules</a> |
| 102 | <ol> |
Daniel Veillard | 9c46682 | 2001-10-25 12:03:39 +0000 | [diff] [blame] | 103 | <li><a href="#reference">How to reference a DTD from a document</a></li> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 104 | <li><a href="#Declaring">Declaring elements</a></li> |
| 105 | <li><a href="#Declaring1">Declaring attributes</a></li> |
| 106 | </ol> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 107 | </li> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 108 | <li><a href="#Some">Some examples</a></li> |
| 109 | <li><a href="#validate">How to validate</a></li> |
| 110 | <li><a href="#Other">Other resources</a></li> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 111 | </ol> |
| 112 | <h3><a name="General5">General overview</a></h3> |
| 113 | <p>Well what is validation and what is a DTD ?</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 114 | <p>DTD is the acronym for Document Type Definition. This is a description of |
Daniel Veillard | 63d8314 | 2002-05-20 06:51:05 +0000 | [diff] [blame] | 115 | the content for a family of XML files. This is part of the XML 1.0 |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 116 | specification, and allows one to describe and verify that a given document |
| 117 | instance conforms to the set of rules detailing its structure and content.</p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 118 | <p>Validation is the process of checking a document against a DTD (more |
| 119 | generally against a set of construction rules).</p> |
| 120 | <p>The validation process and building DTDs are the two most difficult parts |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 121 | of the XML life cycle. Briefly a DTD defines all the possible elements to be |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 122 | found within your document, what is the formal shape of your document tree |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 123 | (by defining the allowed content of an element; either text, a regular |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 124 | expression for the allowed list of children, or mixed content i.e. both text |
Daniel Veillard | 42766c0 | 2002-08-22 20:52:17 +0000 | [diff] [blame] | 125 | and children). The DTD also defines the valid attributes for all elements and |
| 126 | the types of those attributes.</p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 127 | <h3><a name="definition1">The definition</a></h3> |
| 128 | <p>The <a href="http://www.w3.org/TR/REC-xml">W3C XML Recommendation</a> (<a href="http://www.xml.com/axml/axml.html">Tim Bray's annotated version of |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 129 | Rev1</a>):</p> |
| 130 | <ul> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 131 | <li><a href="http://www.w3.org/TR/REC-xml#elemdecls">Declaring |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 132 | elements</a></li> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 133 | <li><a href="http://www.w3.org/TR/REC-xml#attdecls">Declaring |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 134 | attributes</a></li> |
| 135 | </ul> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 136 | <p>(unfortunately) all this is inherited from the SGML world, the syntax is |
| 137 | ancient...</p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 138 | <h3><a name="Simple1">Simple rules</a></h3> |
Daniel Veillard | 42766c0 | 2002-08-22 20:52:17 +0000 | [diff] [blame] | 139 | <p>Writing DTDs can be done in many ways. The rules to build them if you need |
| 140 | something permanent or something which can evolve over time can be radically |
| 141 | different. Really complex DTDs like DocBook ones are flexible but quite |
| 142 | harder to design. I will just focus on DTDs for a formats with a fixed simple |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 143 | structure. It is just a set of basic rules, and definitely not exhaustive nor |
Daniel Veillard | 63d8314 | 2002-05-20 06:51:05 +0000 | [diff] [blame] | 144 | usable for complex DTD design.</p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 145 | <h4> |
| 146 | <a name="reference1">How to reference a DTD from a document</a>:</h4> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 147 | <p>Assuming the top element of the document is <code>spec</code> and the dtd |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 148 | is placed in the file <code>mydtd</code> in the subdirectory |
| 149 | <code>dtds</code> of the directory from where the document were loaded:</p> |
| 150 | <p><code><!DOCTYPE spec SYSTEM "dtds/mydtd"></code></p> |
Daniel Veillard | 64e7390 | 2000-11-24 13:28:38 +0000 | [diff] [blame] | 151 | <p>Notes:</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 152 | <ul> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 153 | <li>The system string is actually an URI-Reference (as defined in <a href="http://www.ietf.org/rfc/rfc2396.txt">RFC 2396</a>) so you can use a |
| 154 | full URL string indicating the location of your DTD on the Web. This is a |
| 155 | really good thing to do if you want others to validate your document.</li> |
| 156 | <li>It is also possible to associate a <code>PUBLIC</code> identifier (a |
Daniel Veillard | 63d8314 | 2002-05-20 06:51:05 +0000 | [diff] [blame] | 157 | magic string) so that the DTD is looked up in catalogs on the client side |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 158 | without having to locate it on the web.</li> |
| 159 | <li>A DTD contains a set of element and attribute declarations, but they |
Daniel Veillard | 63d8314 | 2002-05-20 06:51:05 +0000 | [diff] [blame] | 160 | don't define what the root of the document should be. This is explicitly |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 161 | told to the parser/validator as the first element of the |
| 162 | <code>DOCTYPE</code> declaration.</li> |
| 163 | </ul> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 164 | <h4> |
| 165 | <a name="Declaring2">Declaring elements</a>:</h4> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 166 | <p>The following declares an element <code>spec</code>:</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 167 | <p><code><!ELEMENT spec (front, body, back?)></code></p> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 168 | <p>It also expresses that the spec element contains one <code>front</code>, |
Daniel Veillard | c0801af | 2002-05-28 16:28:42 +0000 | [diff] [blame] | 169 | one <code>body</code> and one optional <code>back</code> children elements in |
| 170 | this order. The declaration of one element of the structure and its content |
| 171 | are done in a single declaration. Similarly the following declares |
Daniel Veillard | 64e7390 | 2000-11-24 13:28:38 +0000 | [diff] [blame] | 172 | <code>div1</code> elements:</p> |
Daniel Veillard | 5173727 | 2002-01-23 23:10:38 +0000 | [diff] [blame] | 173 | <p><code><!ELEMENT div1 (head, (p | list | note)*, div2?)></code></p> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 174 | <p>which means div1 contains one <code>head</code> then a series of optional |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 175 | <code>p</code>, <code>list</code>s and <code>note</code>s and then an |
| 176 | optional <code>div2</code>. And last but not least an element can contain |
| 177 | text:</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 178 | <p><code><!ELEMENT b (#PCDATA)></code></p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 179 | <p> |
| 180 | <code>b</code> contains text or being of mixed content (text and elements |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 181 | in no particular order):</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 182 | <p><code><!ELEMENT p (#PCDATA|a|ul|b|i|em)*></code></p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 183 | <p> |
| 184 | <code>p </code>can contain text or <code>a</code>, <code>ul</code>, |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 185 | <code>b</code>, <code>i </code>or <code>em</code> elements in no particular |
| 186 | order.</p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 187 | <h4> |
| 188 | <a name="Declaring1">Declaring attributes</a>:</h4> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 189 | <p>Again the attributes declaration includes their content definition:</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 190 | <p><code><!ATTLIST termdef name CDATA #IMPLIED></code></p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 191 | <p>means that the element <code>termdef</code> can have a <code>name</code> |
Daniel Veillard | 63d8314 | 2002-05-20 06:51:05 +0000 | [diff] [blame] | 192 | attribute containing text (<code>CDATA</code>) and which is optional |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 193 | (<code>#IMPLIED</code>). The attribute value can also be defined within a |
| 194 | set:</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 195 | <p><code><!ATTLIST list type (bullets|ordered|glossary) |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 196 | "ordered"></code></p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 197 | <p>means <code>list</code> element have a <code>type</code> attribute with 3 |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 198 | allowed values "bullets", "ordered" or "glossary" and which default to |
Daniel Veillard | 63d8314 | 2002-05-20 06:51:05 +0000 | [diff] [blame] | 199 | "ordered" if the attribute is not explicitly specified.</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 200 | <p>The content type of an attribute can be text (<code>CDATA</code>), |
| 201 | anchor/reference/references |
| 202 | (<code>ID</code>/<code>IDREF</code>/<code>IDREFS</code>), entity(ies) |
| 203 | (<code>ENTITY</code>/<code>ENTITIES</code>) or name(s) |
| 204 | (<code>NMTOKEN</code>/<code>NMTOKENS</code>). The following defines that a |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 205 | <code>chapter</code> element can have an optional <code>id</code> attribute |
| 206 | of type <code>ID</code>, usable for reference from attribute of type |
| 207 | IDREF:</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 208 | <p><code><!ATTLIST chapter id ID #IMPLIED></code></p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 209 | <p>The last value of an attribute definition can be <code>#REQUIRED |
| 210 | </code>meaning that the attribute has to be given, <code>#IMPLIED</code> |
| 211 | meaning that it is optional, or the default value (possibly prefixed by |
| 212 | <code>#FIXED</code> if it is the only allowed).</p> |
Daniel Veillard | 64e7390 | 2000-11-24 13:28:38 +0000 | [diff] [blame] | 213 | <p>Notes:</p> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 214 | <ul> |
| 215 | <li>Usually the attributes pertaining to a given element are declared in a |
Daniel Veillard | 64e7390 | 2000-11-24 13:28:38 +0000 | [diff] [blame] | 216 | single expression, but it is just a convention adopted by a lot of DTD |
| 217 | writers: |
| 218 | <pre><!ATTLIST termdef |
| 219 | id ID #REQUIRED |
| 220 | name CDATA #IMPLIED></pre> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 221 | <p>The previous construct defines both <code>id</code> and |
| 222 | <code>name</code> attributes for the element <code>termdef</code>.</p> |
| 223 | </li> |
| 224 | </ul> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 225 | <h3><a name="Some1">Some examples</a></h3> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 226 | <p>The directory <code>test/valid/dtds/</code> in the libxml distribution |
Daniel Veillard | 42766c0 | 2002-08-22 20:52:17 +0000 | [diff] [blame] | 227 | contains some complex DTD examples. The example in the file |
| 228 | <code>test/valid/dia.xml</code> shows an XML file where the simple DTD is |
| 229 | directly included within the document.</p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 230 | <h3><a name="validate1">How to validate</a></h3> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 231 | <p>The simplest way is to use the xmllint program included with libxml. The |
| 232 | <code>--valid</code> option turns-on validation of the files given as input. |
| 233 | For example the following validates a copy of the first revision of the XML |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 234 | 1.0 specification:</p> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 235 | <p><code>xmllint --valid --noout test/valid/REC-xml-19980210.xml</code></p> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 236 | <p>the -- noout is used to disable output of the resulting tree.</p> |
Daniel Veillard | 42766c0 | 2002-08-22 20:52:17 +0000 | [diff] [blame] | 237 | <p>The <code>--dtdvalid dtd</code> allows validation of the document(s) |
| 238 | against a given DTD.</p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 239 | <p>Libxml exports an API to handle DTDs and validation, check the <a href="http://xmlsoft.org/html/libxml-valid.html">associated |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 240 | description</a>.</p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 241 | <h3><a name="Other1">Other resources</a></h3> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 242 | <p>DTDs are as old as SGML. So there may be a number of examples on-line, I |
| 243 | will just list one for now, others pointers welcome:</p> |
Daniel Veillard | 0b28e88 | 2002-07-24 23:47:05 +0000 | [diff] [blame] | 244 | <ul> |
| 245 | <li><a href="http://www.xml101.com:8081/dtd/">XML-101 DTD</a></li> |
| 246 | </ul> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 247 | <p>I suggest looking at the examples found under test/valid/dtd and any of |
| 248 | the large number of books available on XML. The dia example in test/valid |
| 249 | should be both simple and complete enough to allow you to build your own.</p> |
| 250 | <p> |
Daniel Veillard | 3f4c40f | 2002-02-13 09:19:28 +0000 | [diff] [blame] | 251 | <p><a href="bugs.html">Daniel Veillard</a></p> |
Daniel Veillard | b8cfbd1 | 2001-10-25 10:53:28 +0000 | [diff] [blame] | 252 | </td></tr></table></td></tr></table></td></tr></table></td> |
| 253 | </tr></table></td></tr></table> |
Daniel Veillard | 300f7d6 | 2000-11-24 13:04:04 +0000 | [diff] [blame] | 254 | </body> |
| 255 | </html> |