How do I make a method work for any enum

Question

I have the following code, where ApplicationType is an enum. I have the same repeated code (everything except the parameter types) on many other enums. Whats the best way to consolidate this code?

 private static string GetSelected(ApplicationType type_, ApplicationType checkedType_)
    {
        if (type_ == checkedType_)
        {
            return " selected ";
        }
        else
        {
            return "";
        }
    }

Answer 1

It's hard to do this through a generic constraint at compile time because an enum is really an int. You'll need to restrict the values at runtime.

Answer 2

For equality on an emum? Simply:

public static string GetSelected<T>(T x, T y) {
    return EqualityComparer<T>.Default.Equals(x,y) ? " selected " : "";
}

You could add where T : struct to the top line, but there isn't a need to do that.

For a full example including demo:

using System;
using System.Collections.Generic;
static class Program {
    static void Main() {
        ApplicationType value = ApplicationType.B;
        Console.WriteLine("A: " + GetSelected(value, ApplicationType.A));
        Console.WriteLine("B: " + GetSelected(value, ApplicationType.B));
        Console.WriteLine("C: " + GetSelected(value, ApplicationType.C));
    }
    private static string GetSelected<T>(T x, T y) {
        return EqualityComparer<T>.Default.Equals(x, y) ? " selected " : "";
    }
    enum ApplicationType { A, B, C }
}

Answer 3

Is this appropriate for your needs?

private static string GetSelected<T>(T type_, T checkedType_)
    where T: struct
{
    if(type_.Equals(checkedType_))
        return " selected ";
    return "";
}