private static void ImplementSharedExecuter(MethodBuilderContext context, MethodInfo initMethod, MethodInfo execMethod)
{
FieldBuilder field = null;
if (initMethod != null)
{
field = context.TypeBuilder.DefineField("__methodField_" + context.Method.Name + context.Method.GetHashCode().ToString(), initMethod.ReturnType, FieldAttributes.Private);
// Load instance for initializer
context.InitMethodGenerator.Emit(OpCodes.Ldarg_0);
context.InitMethodGenerator.Emit(OpCodes.Ldarg_0);
context.InitMethodGenerator.Emit(OpCodes.Ldsfld, context.MethodInfoField);
context.InitMethodGenerator.EmitCall(OpCodes.Call, initMethod, null); // Call init method
context.InitMethodGenerator.Emit(OpCodes.Stfld, field); // Store result in field
}
// Create object array to hold all parameters and load on stack
var parametersArray = context.ExecMethodGenerator.EmitParametersArray(context.Method);
// Call executer(layer, state, params)
context.ExecMethodGenerator.Emit(OpCodes.Ldarg_0); // Load instance as first param to execute
if (field != null)
{
context.ExecMethodGenerator.Emit(OpCodes.Ldarg_0); // Load instance for load field
context.ExecMethodGenerator.Emit(OpCodes.Ldfld, field); // Load infos array
}
else
{
context.ExecMethodGenerator.Emit(OpCodes.Ldsfld, context.MethodInfoField);
}
context.ExecMethodGenerator.Emit(OpCodes.Ldloc, parametersArray); // Load params as third param for execute
context.ExecMethodGenerator.EmitCall(OpCodes.Call, execMethod, null); // Call execute method
// Handle return value
if (context.Method.ReturnType == typeof(void))
{
context.ExecMethodGenerator.Emit(OpCodes.Pop);
}
else if (context.Method.ReturnType.IsValueType)
{
context.ExecMethodGenerator.Emit(OpCodes.Unbox_Any, context.Method.ReturnType);
}
}
private static void ImplementTarget(MethodBuilderContext context, string targetMemberName, Func <MethodInfo, MethodInfo> targetMethodSelector)
{
// Find target method
MethodInfo targetMethod = targetMethodSelector(context.Method);
if (targetMethod == null)
{
throw new ArgumentException("Target method for interface method {0} not found.", context.Method.Name);
}
// If method is instance, we need to find target instance and load it on stack
if (!targetMethod.IsStatic)
{
MemberInfo getTargetMember = context.BaseClass.GetMember(targetMemberName, BindingFlags.Instance | BindingFlags.Static | BindingFlags.NonPublic | BindingFlags.Public).Single();
context.ExecMethodGenerator.Emit(OpCodes.Ldarg_0);
if (getTargetMember.MemberType == MemberTypes.Field)
{
context.ExecMethodGenerator.Emit(OpCodes.Ldfld, (FieldInfo)getTargetMember);
}
else if (getTargetMember.MemberType == MemberTypes.Property)
{
context.ExecMethodGenerator.EmitCall(OpCodes.Call, ((PropertyInfo)getTargetMember).GetGetMethod(), null);
}
else
{
context.ExecMethodGenerator.EmitCall(OpCodes.Call, (MethodInfo)getTargetMember, null);
}
}
// Load all parameters
for (int i = 1; i <= context.Method.GetParameters().Length; i++)
{
context.ExecMethodGenerator.Emit(OpCodes.Ldarg, i);
}
// Call method and return
context.ExecMethodGenerator.EmitCall(OpCodes.Call, targetMethod, null);
context.ExecMethodGenerator.Emit(OpCodes.Ret);
}