public HookPropertySetResult HookPropertySet(GenerateEventResult generateEventResult, string addToType, string propertyName)
{
var addEventToType = _module.Types.Single(t => t.Name == addToType);
if (addEventToType.Events.Any(ev => ev.Name == generateEventResult.EventDefinition.Name))
{
return(new HookPropertySetResult($"'{generateEventResult.EventDefinition.FullName}' already existing in type '{addToType}', skipping..."));
}
addEventToType.Fields.Add(generateEventResult.FieldDefinition);
addEventToType.Methods.Add(generateEventResult.EventDefinition.AddMethod);
addEventToType.Methods.Add(generateEventResult.EventDefinition.RemoveMethod);
addEventToType.Events.Add(generateEventResult.EventDefinition);
System.Console.WriteLine($"Added event: {generateEventResult.EventDefinition.Name} to '{addEventToType.Name}'");
InjectEventCallAtPropertySetterStart(propertyName, addEventToType, generateEventResult);
System.Console.WriteLine($"Event: {generateEventResult.EventDefinition.Name} will be called on start property-setter '{addEventToType.Name}:{propertyName}'");
return(new HookPropertySetResult(null));
}
private void InjectEventCallAtPropertySetterStart(string propertyName, TypeDefinition addEventToType, GenerateEventResult generateEventResult)
{
//change existing method to call into event
var setMethod = addEventToType.Methods.Single(m => m.Name == $"set_{propertyName}");
var il = setMethod.Body.GetILProcessor();
var firstInstruction = setMethod.Body.Instructions.First();
var loadThisArgForEventCall = il.Create(OpCodes.Ldarg_0);
il.InsertBefore(firstInstruction, il.Create(OpCodes.Ldarg_0));
il.InsertBefore(firstInstruction, il.Create(OpCodes.Ldfld, generateEventResult.FieldDefinition));
il.InsertBefore(firstInstruction, il.Create(OpCodes.Dup));
il.InsertBefore(firstInstruction, il.Create(OpCodes.Brtrue, loadThisArgForEventCall));
il.InsertBefore(firstInstruction, il.Create(OpCodes.Pop));
il.InsertBefore(firstInstruction, il.Create(OpCodes.Br, firstInstruction));
il.InsertBefore(firstInstruction, loadThisArgForEventCall);
il.InsertBefore(firstInstruction, il.Create(OpCodes.Ldarg_1));
var genericInvoke = CreateGenericInvokeMethodReference(generateEventResult.GenericHandlerParamType, generateEventResult.FieldDefinition);
il.InsertBefore(firstInstruction, il.Create(OpCodes.Callvirt, genericInvoke));
}