Question

I have a C# code like this:

using System;
delegate int anto(int x);
class Anto 
{
    static void Main()
    {
        anto a = square;
        int result = a(3);
        Console.WriteLine(result);
    }
    static int square(int x)
    {
        return x*x;
    }
}

which output’s : 9. Well I’m a novice in C#, so I started to play around with this code and so when I remove the static keyword from the square method, then I’m getting error like this:

An object reference is required to access non-static member `Anto.square(int)'
Compilation failed: 1 error(s), 0 warnings

what causes this error? So if I use delegates I need the method to be static?

I run this code here

Thanks in advance.

Answer 1

Because Main is static, it can only reference other static members. If you remove static from square, it becomes an instance member, and in the static context of Main, there is no instance of any object, so instance members aren’t ‘valid’.

Thankfully there’s nothing crazy going on with delegates, it’s just the way static works – it indicates members are global to a type and not an instance of that type.