High-order Function question... RRS feed

  • Question

  • Hello, I'm newbie to c#, and I was reading on my book that I can pass functions as parameters and receive functions or both... so I'm trying to make an exercise but can't make this work... please help!

    My idea is to create a static function like this:
    public static void TestMethod<T1, TResult>(Func<T1, TResult> myfunction ) {
    Now, the idea is that I can call this static method by providing a function that matches the T1 and the TResult like this:
    Func<string, string> ChangeName = name => $"My name is: {name}";
    TestMethod<string, string>(ChangeName);
    Now my understanding is that inside the TestMethod I received a function, now I can make use of the myfunction and call it to action, am I right? in this case, if I call the function it should return an string (according to my definition), so I think I should be able to do this:
    public static void TestMethod<T1, TResult>(Func<T1, TResult> myfunction ) {
        Console.WriteLine(    myfunction.Invoke()        );
            // or
        Console.WriteLine(    myfunction()    );
    But I can't because it display an error asking for a T1 parameter...

    Monday, April 13, 2020 3:34 AM

All replies

  • The T1 is the input parameter which we need to take as method parameter which you are missing in your method definition:

    public static void TestMethod<T1, TResult>(Func<T1, TResult> myfunction, T1 parameter ) 
        return myfunction(parameter);

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    Monday, April 13, 2020 4:38 AM
  • Hi,

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    Wednesday, April 22, 2020 8:56 AM