How to use generics to pass argument to a non-generic method?

Question

Why does the following code not compile? How can I create a generic method which calls the appropriate "BitConverter.GetBytes" overload based on if the generic type is an "int", "bool", "char", etc.? More generally, how can I create a generic method which calls a non-generic method based on the generic parameter's type?

using System;

public class Test
{
    public static void Main()
    {
      var f = new Foo();
      f.GetBytes(10); // should call BitConverter.GetBytes(int);
      f.GetBytes(true); // should call BitConverter.GetBytes(bool);
      f.GetBytes('A'); // should call BitConverter.GetBytes(char);
    }
}

public class Foo
{
    public byte[] GetBytes <TSource> (TSource input)
    {
      BitConverter.GetBytes(input);
    }
}

Answer 1

More generally, how can I create a generic method which calls a non-generic method based on the generic parameter's type?

In general, you can't, unless the method in question takes System.Object as a parameter. The problem is that the generic isn't constrained to just types that would be allowed by the method call arguments.

The closest you can do is to use runtime binding:

public byte[] GetBytes <TSource> (TSource input)
{
     dynamic obj = input;
     BitConverter.GetBytes(obj);
}

This pushes the method binding logic to runtime, and will throw if there isn't an appropriate method to call.