委托'System.Func< int，int，string>'不带1个参数 [英] Delegate 'System.Func<int,int,string>' does not take 1 arguments

问题描述

我看到了一些关于stackoverflow的类似问题的解决方案，但是看起来每个问题都是唯一的.

I saw some solutions on stackoverflow for similar issues but looks like each problem is unique.

我正在尝试实现全局try/catch，而不是在每个方法上都编写try/catch，但是我一直陷在这个错误中.它适用于一个参数，而不适用于采用多个参数的方法.

I am trying to implement global try/catch instead of writing try/catch on each and every method but I am stuck with this error. It's working fine for one argument and not working for methods taking more than one argument.

class Program
    {
        static void Main(string[] args)
        {  
            int i = 5;
            int j = 10;
            string s1 = GlobalTryCatch(x => square(i), i);
            string s2 = GlobalTryCatch(x => Sum(i,j), i, j); // error here..

            Console.Read();
        }

        private static string square(int i)
        {
            Console.WriteLine(i * i);
            return "1";
        }

        private static string Sum(int i, int j)
        {
            Console.WriteLine(i+j);
            return "1";
        }

        private static string GlobalTryCatch<T1>(Func<T1, string> action, T1 i)
        {
            try
            {
                action.Invoke(i);
                return "success";
            }
            catch (Exception e)
            {
                return "failure";
            }
        }

        private static string GlobalTryCatch<T1, T2>(Func<T1, T2, string> action, T1 i, T2 j)
        {
            try
            {
                action.Invoke(i, j);
                return "success";
            }
            catch (Exception e)
            {
                return "failure";
            }
        }
    }   

推荐答案

string s2 = GlobalTryCatch((x, y) => Sum(i, j), i, j);

编译器无法将原始方法与string GlobalTryCatch<T1>(Func<T1, string> action, T1 i)匹配，因为您的lambda表达式只有一个参数，但是方法签名需要两个参数.解决方法是使用(x, y)，它表示lambda接受两个参数.

The compiler couldn't match your original method with string GlobalTryCatch<T1>(Func<T1, string> action, T1 i) because your lambda expression only had one argument, but the method signature calls for two arguments. The fix is to use (x, y), which indicates that the lambda is taking two arguments.

作为快捷方式，您可以仅提供方法组"，这将导致以下结果:

As a shortcut, you can just provide the "method group", which would result in the following:

string s2 = GlobalTryCatch(Sum, i, j);

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