re: Optimizing Away Repeat XML Namespace Declarations with DataContractSerializer

RobSiklos — Wed, 16 May 2012 15:24:51 GMT

Nevermind - found this: blogs.msdn.com/.../wcf-extensibility-custom-serialization-in-silverlight.aspx

re: Optimizing Away Repeat XML Namespace Declarations with DataContractSerializer

RobSiklos — Mon, 14 May 2012 19:37:49 GMT

This works great - After reading this article (blogs.msdn.com/.../wcf-extensibility-ioperationbehavior.aspx) I was able to implement my custom XmlObjectSerializer on the server.

Now, anybody know how to get this working in Silverlight? It seems that DataContractSerializerOperationBehavior is not available.

re: Optimizing Away Repeat XML Namespace Declarations with DataContractSerializer

Spyrrho — Tue, 27 Apr 2010 00:30:42 GMT

I have this problem now for very large object graphs in WCF data contracts.

How can I make WCF do something similar?

re: Optimizing Away Repeat XML Namespace Declarations with DataContractSerializer

Youssef Moussaoui - MSFT — Mon, 01 Mar 2010 20:16:37 GMT

Hi MattO, the solution offered here should still work for you.

You don't need to specify *all* of the namespaces at the top. You can just feel free to specify any namespace you want.

Namespaces you do specify will always get written out at the top-level. But namespaces that the serializer needs that you don't specify yourself will get written out by the serializer for you whenever they're needed.

re: Optimizing Away Repeat XML Namespace Declarations with DataContractSerializer

MattO — Thu, 25 Feb 2010 01:38:40 GMT

I'm having a similar problem, but its the "http://www.w3.org/2001/XMLSchema" namespace that the DataContractSerializer is repeating. Unfortunately, I don't always know all of the types that I need to use (and prefer to specify the KnownTypes attribute on the DataContracts), so manually adding all of the namespaces to the top of the xml document won't work for me. Instead I just want to use the existing namespaces at the top, but just add the "http://www.w3.org/2001/XMLSchema" namespace.

Any ideas how one would do this?

re: Optimizing Away Repeat XML Namespace Declarations with DataContractSerializer

Aruna_v — Thu, 24 Dec 2009 10:31:30 GMT

Great Article! Refering to the prefix of the namespace can make things easier. Its a good namespace design approach.

re: Optimizing Away Repeat XML Namespace Declarations with DataContractSerializer

Alexandre Mutel — Wed, 12 Aug 2009 17:56:25 GMT

Thanks for this article, it was very helpful to strip namespaces! Here is the code i'm using for a specialized DataContractSerializerExt as you suggest at the end.

[code]

public class DataContractSerializerExt : XmlObjectSerializer

{

private readonly DataContractSerializer serializer;

readonly List<string> namespaces = new List<string>();

public DataContractSerializerExt(Type type)

{

serializer = new DataContractSerializer(type);

InitNamespaces(type, null);

}

public DataContractSerializerExt(Type type, IEnumerable<Type> knownTypes)

{

serializer = new DataContractSerializer(type, knownTypes);

InitNamespaces(type, knownTypes);

}

public DataContractSerializerExt(Type type, string rootName, string rootNamespace)

{

serializer = new DataContractSerializer(type, rootName, rootNamespace);

InitNamespaces(type, null);

}

public DataContractSerializerExt(Type type, XmlDictionaryString rootName, XmlDictionaryString rootNamespace)

{

serializer = new DataContractSerializer(type, rootName, rootNamespace);

InitNamespaces(type, null);

}

public DataContractSerializerExt(Type type, string rootName, string rootNamespace, IEnumerable<Type> knownTypes)

{

serializer = new DataContractSerializer(type, rootName, rootNamespace, knownTypes);

InitNamespaces(type, knownTypes);

}

public DataContractSerializerExt(Type type, XmlDictionaryString rootName, XmlDictionaryString rootNamespace, IEnumerable<Type> knownTypes)

{

serializer = new DataContractSerializer(type, rootName, rootNamespace, knownTypes);

InitNamespaces(type, knownTypes);

}

public DataContractSerializerExt(Type type, IEnumerable<Type> knownTypes, int maxItemsInObjectGraph, bool ignoreExtensionDataObject, bool preserveObjectReferences, IDataContractSurrogate dataContractSurrogate)

{

serializer = new DataContractSerializer(type, knownTypes, maxItemsInObjectGraph, ignoreExtensionDataObject,

preserveObjectReferences, dataContractSurrogate);

InitNamespaces(type, knownTypes);

}

public DataContractSerializerExt(Type type, string rootName, string rootNamespace, IEnumerable<Type> knownTypes, int maxItemsInObjectGraph, bool ignoreExtensionDataObject, bool preserveObjectReferences, IDataContractSurrogate dataContractSurrogate)

{

serializer = new DataContractSerializer(type, rootName, rootNamespace, knownTypes, maxItemsInObjectGraph,

ignoreExtensionDataObject, preserveObjectReferences,

dataContractSurrogate);

InitNamespaces(type, knownTypes);

}

public DataContractSerializerExt(Type type, XmlDictionaryString rootName, XmlDictionaryString rootNamespace, IEnumerable<Type> knownTypes, int maxItemsInObjectGraph, bool ignoreExtensionDataObject, bool preserveObjectReferences, IDataContractSurrogate dataContractSurrogate)

{

serializer = new DataContractSerializer(type, rootName, rootNamespace, knownTypes, maxItemsInObjectGraph,

ignoreExtensionDataObject, preserveObjectReferences,

dataContractSurrogate);

InitNamespaces(type, knownTypes);

}

private void InitNamespaces(Type mainType, IEnumerable<Type> knownTypes)

{

List<Type> types = new List<Type>();

types.Add(mainType);

if ( knownTypes != null)

{

types.AddRange(knownTypes);

}

List<Assembly> assemblies = new List<Assembly>();

foreach (Type type in types)

{

if ( ! assemblies.Contains(type.Assembly))

{

assemblies.Add(type.Assembly);

}

// Add Contract namespace defined at the assembly level

foreach (Assembly assembly in assemblies)

{

Attribute attr = Attribute.GetCustomAttribute(assembly, typeof (ContractNamespaceAttribute));

if ( attr != null )

{

ContractNamespaceAttribute contractNamespaceAttribute = (ContractNamespaceAttribute) attr;

if ( contractNamespaceAttribute.ContractNamespace != null && ! namespaces.Contains(contractNamespaceAttribute.ContractNamespace) )

namespaces.Add(contractNamespaceAttribute.ContractNamespace);

}

// Add Contract namespace defined at the type level

foreach (Type type in types)

{

Attribute attr = Attribute.GetCustomAttribute(type, typeof (DataContractAttribute));

if ( attr != null )

{

DataContractAttribute dataContractAttribute = (DataContractAttribute) attr;

if (dataContractAttribute.Namespace != null && !namespaces.Contains(dataContractAttribute.Namespace))

namespaces.Add(dataContractAttribute.Namespace);

}

public override void WriteObject(Stream stream, object graph)

{

XmlDictionaryWriter writer = XmlDictionaryWriter.CreateTextWriter(stream, Encoding.UTF8, false);

WriteObject(writer, graph);

writer.Flush();

}

public override void WriteObject(XmlDictionaryWriter writer, object graph)

{

WriteStartObject(writer, graph);

// Skip first default namespace (standard xmlns without alias)

// and add the following namespace with x[0-9]+ alias

for (int i = 1; i < namespaces.Count; i++ )

{

string aliasNamespace = "x" + ((i > 1) ? (i-1).ToString() : "");

writer.WriteAttributeString("xmlns", aliasNamespace, null, namespaces[i]);

}

WriteObjectContent(writer, graph);

WriteEndObject(writer);

}

public override void WriteObject(XmlWriter writer, object graph)

{

WriteObject(XmlDictionaryWriter.CreateDictionaryWriter(writer), graph);

}

public override void WriteStartObject(XmlDictionaryWriter writer, object graph)

{

serializer.WriteStartObject(writer, graph);

}

public override void WriteObjectContent(XmlDictionaryWriter writer, object graph)

{

serializer.WriteObjectContent(writer, graph);

}

public override void WriteEndObject(XmlDictionaryWriter writer)

{

serializer.WriteEndObject(writer);

}

public override object ReadObject(XmlDictionaryReader reader, bool verifyObjectName)

{

return serializer.ReadObject(reader, verifyObjectName);

}

public override bool IsStartObject(XmlDictionaryReader reader)

{

return serializer.IsStartObject(reader);

}

[/code]