internal static IHandler CreateHandler(HandlerMethodData handlerData, object eventProxy)
{
var paramType = handlerData.ParameterType;
// Creates Handler<TEvent> type using TEvent from method parameter type
var handlerType = typeof(Handler <>).MakeGenericType(paramType);
// Creates Action<T> type using T from method parameter type
var actionType = typeof(Action <>).MakeGenericType(paramType);
// Creates instance of Action<T> using T from method parameter type
var action = Delegate.CreateDelegate(actionType, eventProxy, handlerData.Method);
// Creates instance of Handler<TEvent> using TEvent param type , handler priority from attribute and action from MethodInfo
var handler = Activator.CreateInstance(handlerType, paramType, handlerData.AttachedAttribute.Priority, action);
return(handler as IHandler);
}
internal static bool TryCreateHandlerData(MethodInfo methodInfo, out HandlerMethodData data)
{
//No attribute found, handler cannot be created
if (!(methodInfo.GetCustomAttributes(typeof(HandlerAttribute), true).FirstOrDefault() is HandlerAttribute attribute))
{
data = null;
return(false);
}
var methodParams = methodInfo.GetParameters();
//Method doesn't mach handler pattern, handler cannot be created
if (methodParams.Length != 1)
{
data = null;
return(false);
}
var methodParameter = methodParams.FirstOrDefault();
var paramType = methodParameter?.ParameterType;
var handlerData = new HandlerMethodData()
{
AttachedAttribute = attribute,
Method = methodInfo,
ParameterType = paramType
};
data = handlerData;
return(true);
}