委托&#39;System.Func <int,int,string> &#39;不带1个参数

Question

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

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";
            }
        }
    }   

Answer 1

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

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.

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

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

Answer 2

You can provide your two-parameter Func like this

string s2 = GlobalTryCatch(Sum, i, j); // error here..

There is no need to add a lambda expression.

Answer 3

You might want to consider handling Application.UnhandledException event and handle your exceptions there.

Your method signatures differ. That is why you cannot use a single implementation of GlobalTryCatch.