我正在尝试实现以下模式函数：
MethodInfo GetMethod( Expression<Func<TTarget,EventHandler<TEventArgs>>> method)
如果需要,我可以提供TTarget的实例
所需的用法是：
public static void Main(string[] args)
{
var methodInfo = GetMethod<Program,EventArgs>(t => t.Method);
Console.WriteLine("Hello,world!");
}
private void Method(object sender,EventArgs e)
{
}
这是我到目前为止所尝试的内容：
private static MethodInfo GetMethod(TTarget target,Expression<Func<TTarget,EventHandler<TEventArgs>>> method)
{
var lambda = method as LambdaExpression;
var body = lambda.Body as UnaryExpression;
var call = body.Operand as MethodCallExpression;
var mInfo = call.Method as MethodInfo;
Console.WriteLine(mInfo);
throw new NotImplementedException();
}
打印出来：
System.Delegate CreateDelegate(System.Type,System.Object,System.Reflection.Met
hodInfo)
解决方法
你在那里的一半.
看下面的代码
看下面的代码
public static void Main(string[] args)
{
var program = new Program();
var methodInfo = GetMethod<Program,EventArgs>(()=> program.Method);
Console.WriteLine(methodInfo.Name);
}
static MethodInfo GetMethod<TTarget,TEventArgs>(Expression<Func<EventHandler<TEventArgs>>> method) where TEventArgs:EventArgs
{
var convert = method.Body as UnaryExpression;
var methodCall = (convert.Operand as MethodCallExpression);
if (methodCall != null && methodCall.Arguments.Count>2 && methodCall.Arguments[2] is ConstantExpression)
{
var methodInfo = (methodCall.Arguments[2]as ConstantExpression).Value as MethodInfo;
return methodInfo;
}
return null;
}
我希望这回答了你的问题.
