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c#parametersvoid

Method With Parameter In Parameter


I want to pass a method with a parameter in a parameter like this. But it still got error and i didn't know what to do.

void WriteInScreen(string text){
    Console.WriteLine(text);
}
void WriteInScreen10Times(string text){
    for (int i = 1; i <= 10; i++){
        Console.WriteLine(text);
    }
}
void CallWriteInScreen(Action Method) {
    Method();
}
void StartCall(){
    //Error: Argument 2: Can't not convert from void to System.Action
    CallWriteInScreen(WriteInScreen("Hello!"));
    CallWriteInScreen(WriteInScreen10Time("Hi!"));
}

This is just my test code, i need to solve this to continue develop my program.


Solution

  • CallWriteToScreen only accepts a delegate that accepts no parameters and produces no result (a.k.a an Action). Not sure whether you want to create a family of CallWriteToScreen methods that accept parameterized Actions:

    void CallWriteInScreen(Action Method) {
        Method();
    }
    void CallWriteInScreen<T1>(Action<T1> Method, T1 arg1) {
        Method(arg1);
    }
    void CallWriteInScreen<T1, T2>(Action<T1, T2> Method, T1 arg1, T2 arg2) {
        Method(arg1, arg2);
    }
    void StartCall(){
        CallWriteInScreen(WriteInScreen, "Hello!");
        CallWriteInScreen(WriteInScreen10Time, "Hi!");
    }
    

    or just want to wrap the eventual method call up:

    void StartCall(){
        CallWriteInScreen(() => WriteInScreen("Hello!"));
        CallWriteInScreen(() => WriteInScreen10Time("Hi!"));
    }