Added the XmlFormatWriter/Reader
diff --git a/src/ProtocolBuffers/Serialization/XmlFormatWriter.cs b/src/ProtocolBuffers/Serialization/XmlFormatWriter.cs
new file mode 100644
index 0000000..5ed9665
--- /dev/null
+++ b/src/ProtocolBuffers/Serialization/XmlFormatWriter.cs
@@ -0,0 +1,166 @@
+using System;
+using System.IO;
+using System.Xml;
+using Google.ProtocolBuffers.Descriptors;
+
+namespace Google.ProtocolBuffers.Serialization
+{
+ /// <summary>
+ /// Writes a proto buffer to an XML document or fragment. .NET 3.5 users may also
+ /// use this class to produce Json by setting the options to support Json and providing
+ /// an XmlWriter obtained from <see cref="System.Runtime.Serialization.Json.JsonReaderWriterFactory"/>.
+ /// </summary>
+ public class XmlFormatWriter : AbstractTextWriter
+ {
+ public const string DefaultRootElementName = "root";
+ private const int NestedArrayFlag = 0x0001;
+ private readonly XmlWriter _output;
+ private string _rootElementName;
+
+ static XmlWriterSettings DefaultSettings
+ {
+ get { return new XmlWriterSettings() {CheckCharacters = false, NewLineHandling = NewLineHandling.Entitize}; }
+ }
+
+ /// <summary>
+ /// Constructs the XmlFormatWriter to write to the given TextWriter
+ /// </summary>
+ public XmlFormatWriter(TextWriter output) : this(XmlWriter.Create(output, DefaultSettings)) { }
+ /// <summary>
+ /// Constructs the XmlFormatWriter to write to the given stream
+ /// </summary>
+ public XmlFormatWriter(Stream output) : this(XmlWriter.Create(output, DefaultSettings)) { }
+ /// <summary>
+ /// Constructs the XmlFormatWriter to write to the given XmlWriter
+ /// </summary>
+ public XmlFormatWriter(XmlWriter output)
+ {
+ _output = output;
+ _rootElementName = DefaultRootElementName;
+ }
+
+ /// <summary>
+ /// Closes the underlying XmlTextWriter
+ /// </summary>
+ protected override void Dispose(bool disposing)
+ {
+ if(disposing)
+ _output.Close();
+ }
+
+ /// <summary>
+ /// Gets or sets the default element name to use when using the Merge<TBuilder>()
+ /// </summary>
+ public string RootElementName
+ {
+ get { return _rootElementName; }
+ set { ThrowHelper.ThrowIfNull(value, "RootElementName"); _rootElementName = value; }
+ }
+
+ /// <summary>
+ /// Gets or sets the options to use while generating the XML
+ /// </summary>
+ public XmlWriterOptions Options { get; set; }
+
+ private bool TestOption(XmlWriterOptions option) { return (Options & option) != 0; }
+
+ /// <summary>
+ /// Writes a message as an element using the name defined in <see cref="RootElementName"/>
+ /// </summary>
+ public override void WriteMessage(IMessageLite message)
+ { WriteMessage(_rootElementName, message); }
+
+ /// <summary>
+ /// Writes a message as an element with the given name
+ /// </summary>
+ public override void WriteMessage(string elementName, IMessageLite message)
+ {
+ if (TestOption(XmlWriterOptions.OutputJsonTypes))
+ {
+ _output.WriteStartElement("root"); // json requires this is the root-element
+ _output.WriteAttributeString("type", "object");
+ }
+ else
+ _output.WriteStartElement(elementName);
+
+ message.WriteTo(this);
+ _output.WriteEndElement();
+ _output.Flush();
+ }
+
+ /// <summary>
+ /// Writes a message
+ /// </summary>
+ protected override void WriteMessageOrGroup(string field, IMessageLite message)
+ {
+ _output.WriteStartElement(field);
+
+ if (TestOption(XmlWriterOptions.OutputJsonTypes))
+ _output.WriteAttributeString("type", "object");
+
+ message.WriteTo(this);
+ _output.WriteEndElement();
+ }
+
+ /// <summary>
+ /// Writes a String value
+ /// </summary>
+ protected override void WriteAsText(string field, string textValue, object typedValue)
+ {
+ _output.WriteStartElement(field);
+
+ if (TestOption(XmlWriterOptions.OutputJsonTypes))
+ {
+ if (typedValue is int || typedValue is uint || typedValue is long || typedValue is ulong || typedValue is double || typedValue is float)
+ _output.WriteAttributeString("type", "number");
+ else if (typedValue is bool)
+ _output.WriteAttributeString("type", "boolean");
+ }
+ _output.WriteString(textValue);
+
+ //Empty strings should not be written as empty elements '<item/>', rather as '<item></item>'
+ if (_output.WriteState == WriteState.Element)
+ _output.WriteRaw("");
+
+ _output.WriteEndElement();
+ }
+
+ /// <summary>
+ /// Writes an array of field values
+ /// </summary>
+ protected override void WriteArray(FieldType fieldType, string field, System.Collections.IEnumerable items)
+ {
+ //see if it's empty
+ System.Collections.IEnumerator eitems = items.GetEnumerator();
+ try { if (!eitems.MoveNext()) return; }
+ finally
+ { if (eitems is IDisposable) ((IDisposable) eitems).Dispose(); }
+
+ if (TestOption(XmlWriterOptions.OutputNestedArrays | XmlWriterOptions.OutputJsonTypes))
+ {
+ _output.WriteStartElement(field);
+ if (TestOption(XmlWriterOptions.OutputJsonTypes))
+ _output.WriteAttributeString("type", "array");
+
+ base.WriteArray(fieldType, "item", items);
+ _output.WriteEndElement();
+ }
+ else
+ base.WriteArray(fieldType, field, items);
+ }
+
+ /// <summary>
+ /// Writes a System.Enum by the numeric and textual value
+ /// </summary>
+ protected override void WriteEnum(string field, int number, string name)
+ {
+ _output.WriteStartElement(field);
+
+ if (!TestOption(XmlWriterOptions.OutputJsonTypes) && TestOption(XmlWriterOptions.OutputEnumValues))
+ _output.WriteAttributeString("value", XmlConvert.ToString(number));
+
+ _output.WriteString(name);
+ _output.WriteEndElement();
+ }
+ }
+}