static IILMethod GenerateAddRemoveEvent(IILDynamicType typeBuilder, IILField fieldBuilder, bool add)
{
Type typePropertyChangedEventHandler = typeof(PropertyChangedEventHandler);
EventInfo eventPropertyChanged = typeof(INotifyPropertyChanged).GetEvent("PropertyChanged");
var methodBuilder = typeBuilder.DefineMethod((add ? "add" : "remove") + "_PropertyChanged",
typeof(void), new[] { typePropertyChangedEventHandler },
MethodAttributes.Public | MethodAttributes.Virtual | MethodAttributes.SpecialName |
MethodAttributes.HideBySig | MethodAttributes.NewSlot | MethodAttributes.Final);
var ilGenerator = methodBuilder.Generator;
ilGenerator.DeclareLocal(typePropertyChangedEventHandler);
ilGenerator.DeclareLocal(typePropertyChangedEventHandler);
ilGenerator.DeclareLocal(typePropertyChangedEventHandler);
var label = ilGenerator.DefineLabel();
ilGenerator
.Ldarg(0)
.Ldfld(fieldBuilder)
.Stloc(0)
.Mark(label)
.Ldloc(0)
.Stloc(1)
.Ldloc(1)
.Ldarg(1)
.Call(add
? GetMethodInfo(() => Delegate.Combine(null, null))
: GetMethodInfo(() => Delegate.Remove(null, null)))
.Castclass(typePropertyChangedEventHandler)
.Stloc(2)
.Ldarg(0)
.Ldflda(fieldBuilder)
.Ldloc(2)
.Ldloc(1);
PropertyChangedEventHandler stub = null;
ilGenerator
.Call(() => Interlocked.CompareExchange(ref stub, null, null))
.Stloc(0)
.Ldloc(0)
.Ldloc(1)
.BneUnS(label)
.Ret();
typeBuilder.DefineMethodOverride(methodBuilder,
add ? eventPropertyChanged.GetAddMethod() : eventPropertyChanged.GetRemoveMethod());
return(methodBuilder);
}
public void Emit(OpCode opCode, IILField ilField)
{
_ilGenerator.Emit(opCode, ((IILFieldPrivate)ilField).TrueField);
}
public static IILGen Stsfld(this IILGen il, IILField fieldInfo)
{
il.Emit(OpCodes.Stsfld, fieldInfo);
return(il);
}
public static IILGen Ldflda(this IILGen il, IILField fieldInfo)
{
il.Emit(OpCodes.Ldflda, fieldInfo);
return(il);
}
public EmitILField(OpCode opCode, IILField ilField)
{
_opCode = opCode;
_ilField = ilField;
}
public void Emit(OpCode opCode, IILField ilField)
{
_instructions.Add(new EmitILField(opCode, ilField));
}
public void Emit(OpCode opCode, IILField ilField)
{
_ilGenerator.Emit(opCode, ((IILFieldPrivate)ilField).TrueField);
}
public void Emit(OpCode opCode, IILField ilField)
{
_sourceCodeWriter.MarkAndWriteLine(_ilGenerator,
$"{opCode} field {ilField.FieldType.ToSimpleName()} {ilField.Name}");
_ilGenerator.Emit(opCode, ((IILFieldPrivate)ilField).TrueField);
}
