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public class Post_79533008_cb7f_478d_9f34_24ed85f5cd51
{
[DataContract]
public class MyHolder
{
[DataMember]
public object Value;
public override string ToString()
{
return string.Format("MyHolder[Value={0}]", this.Value);
}
}
[ServiceContract]
public interface ITest
{
[OperationContract]
MyHolder EchoHolder(MyHolder holder);
}
public class Service : ITest
{
public MyHolder EchoHolder(MyHolder holder)
{
return holder;
}
}
private static void SetResolver(ServiceEndpoint endpoint)
{
foreach (var operation in endpoint.Contract.Operations)
{
DataContractSerializerOperationBehavior dcsob = operation.Behaviors.Find<DataContractSerializerOperationBehavior>();
if (dcsob != null)
{
dcsob.DataContractResolver = new DynamicTypeResolver(ReflectionEmitHelper.CreatePersonType());
}
}
}
public static void Test()
{
string baseAddress = "http://" + Environment.MachineName + ":8000/Service";
ServiceHost host = new ServiceHost(typeof(Service), new Uri(baseAddress));
ServiceEndpoint endpoint = host.AddServiceEndpoint(typeof(ITest), new BasicHttpBinding(), "");
SetResolver(endpoint);
host.Open();
Console.WriteLine("Host opened");
ChannelFactory<ITest> factory = new ChannelFactory<ITest>(new BasicHttpBinding(), new EndpointAddress(baseAddress));
SetResolver(factory.Endpoint);
ITest proxy = factory.CreateChannel();
Type personType = ReflectionEmitHelper.CreatePersonType();
object person = Activator.CreateInstance(personType);
personType.GetProperty("Name").SetValue(person, "John Doe", null);
personType.GetProperty("Age").SetValue(person, 22, null);
Console.WriteLine("Person: {0}", person);
MyHolder holder = new MyHolder { Value = person };
Console.WriteLine("Sending holder over the wire: {0}", holder);
var newHolder = proxy.EchoHolder(holder);
Console.WriteLine("Received holder over the wire: {0}", newHolder);
((IClientChannel)proxy).Close();
factory.Close();
Console.Write("Press ENTER to close the host");
Console.ReadLine();
host.Close();
}
class DynamicTypeResolver : DataContractResolver
{
Type dynamicType;
public DynamicTypeResolver(Type dynamicType)
{
this.dynamicType = dynamicType;
}
public override Type ResolveName(string typeName, string typeNamespace, Type declaredType, DataContractResolver knownTypeResolver)
{
if (typeNamespace == "http://dynamic/" + ReflectionEmitHelper.AssemblyName && typeName == this.dynamicType.Name)
{
return this.dynamicType;
}
else
{
return knownTypeResolver.ResolveName(typeName, typeNamespace, declaredType, null);
}
}
public override bool TryResolveType(Type type, Type declaredType, DataContractResolver knownTypeResolver, out XmlDictionaryString typeName, out XmlDictionaryString typeNamespace)
{
if (type.Assembly.GetName().Name == ReflectionEmitHelper.AssemblyName)
{
XmlDictionary dic = new XmlDictionary();
typeName = dic.Add(type.Name);
typeNamespace = dic.Add("http://dynamic/" + ReflectionEmitHelper.AssemblyName);
return true;
}
else
{
return knownTypeResolver.TryResolveType(type, declaredType, null, out typeName, out typeNamespace);
}
}
}
static class ReflectionEmitHelper
{
public const string AssemblyName = "MyReflectionEmitAssembly";
static Type personType;
internal static Type CreatePersonType()
{
if (personType == null)
{
AppDomain myDomain = AppDomain.CurrentDomain;
AssemblyName myAsmName = new AssemblyName(AssemblyName);
AssemblyBuilder myAssembly =
myDomain.DefineDynamicAssembly(myAsmName,
AssemblyBuilderAccess.RunAndSave);
ModuleBuilder myModule =
myAssembly.DefineDynamicModule(myAsmName.Name,
myAsmName.Name + ".dll");
// public class Person
TypeBuilder personTypeBuilder =
myModule.DefineType("Person", TypeAttributes.Public);
// Add [DataContract] to the type
Type dcaType = typeof(DataContractAttribute);
CustomAttributeBuilder dataContractBuilder = new CustomAttributeBuilder(
dcaType.GetConstructor(Type.EmptyTypes),
new object[0],
new PropertyInfo[] { dcaType.GetProperty("Name"), dcaType.GetProperty("Namespace") },
new object[] { "Person", "http://my.dynamic.namespace" });
personTypeBuilder.SetCustomAttribute(dataContractBuilder);
// Define some fields
FieldBuilder nameField =
personTypeBuilder.DefineField(
"name",
typeof(string),
FieldAttributes.Private);
FieldBuilder ageField =
personTypeBuilder.DefineField(
"age",
typeof(int),
FieldAttributes.Private);
// Define the public properties
MethodBuilder get_Name;
MethodBuilder get_Age;
PropertyBuilder nameProperty = CreateProperty(personTypeBuilder, "Name", nameField, out get_Name);
PropertyBuilder ageProperty = CreateProperty(personTypeBuilder, "Age", ageField, out get_Age);
// Override ToString
MethodBuilder toString = personTypeBuilder.DefineMethod(
"ToString",
MethodAttributes.Public | MethodAttributes.HideBySig | MethodAttributes.Virtual,
typeof(string),
Type.EmptyTypes);
MethodInfo stringFormat = typeof(string).GetMethod(
"Format",
BindingFlags.Static | BindingFlags.Public,
null,
new Type[] { typeof(string), typeof(object), typeof(object) },
null);
ILGenerator toStringIL = toString.GetILGenerator();
toStringIL.Emit(OpCodes.Ldstr, "Person[Name={0},Age={1}]");
toStringIL.Emit(OpCodes.Ldarg_0);
toStringIL.Emit(OpCodes.Call, get_Name);
toStringIL.Emit(OpCodes.Ldarg_0);
toStringIL.Emit(OpCodes.Call, get_Age);
toStringIL.Emit(OpCodes.Box, typeof(int));
toStringIL.Emit(OpCodes.Call, stringFormat);
toStringIL.Emit(OpCodes.Ret);
personType = personTypeBuilder.CreateType();
}
return personType;
}
private static PropertyBuilder CreateProperty(TypeBuilder typeBuilder, string propertyName, FieldBuilder backingField, out MethodBuilder getter)
{
Type propertyType = backingField.FieldType;
PropertyBuilder property = typeBuilder.DefineProperty(
propertyName,
PropertyAttributes.None,
propertyType,
Type.EmptyTypes);
Type dmaType = typeof(DataMemberAttribute);
CustomAttributeBuilder dataMemberAttribute = new CustomAttributeBuilder(
dmaType.GetConstructor(Type.EmptyTypes),
new object[0],
new PropertyInfo[] { dmaType.GetProperty("Name") },
new object[] { propertyName });
property.SetCustomAttribute(dataMemberAttribute);
MethodAttributes getSetAttr = MethodAttributes.Public | MethodAttributes.SpecialName | MethodAttributes.HideBySig;
MethodBuilder getMethod = typeBuilder.DefineMethod("get_" + propertyName, getSetAttr, propertyType, Type.EmptyTypes);
MethodBuilder setMethod = typeBuilder.DefineMethod("set_" + propertyName, getSetAttr, null, new Type[] { propertyType });
getter = getMethod;
ILGenerator getIL = getMethod.GetILGenerator();
getIL.Emit(OpCodes.Ldarg_0);
getIL.Emit(OpCodes.Ldfld, backingField);
getIL.Emit(OpCodes.Ret);
ILGenerator setIL = setMethod.GetILGenerator();
setIL.Emit(OpCodes.Ldarg_0);
setIL.Emit(OpCodes.Ldarg_1);
setIL.Emit(OpCodes.Stfld, backingField);
setIL.Emit(OpCodes.Ret);
property.SetSetMethod(setMethod);
property.SetGetMethod(getMethod);
return property;
}
}
} |
