Retrieving the MethodInfo of of the correct overload of a generic method

Question

I have this type that contains two overloads of a generic method. I like to retrieve one of the overloads (with the Func parameter) using reflection. T

Answer 1

I don't think you can do this directly using GetMethod. I suspect you'll have to iterate over all the methods called Bar, then:

• Check that the method has one type parameter
• Check that the method has one normal parameter
• Use the type parameter to make a Func (with typeof(Func<>).MakeGenericType) and check that the parameter type matches that.

LINQ is good for this sort of thing. Complete sample:

using System;
using System.Reflection;
using System.Linq;

public class Foo
{
    public void Bar(Func f) { }
    public void Bar(Action a) { }
}

class Test
{
    static void Main()
    {
        var methods = from method in typeof(Foo).GetMethods()
                      where method.Name == "Bar"
                      let typeArgs = method.GetGenericArguments()
                      where typeArgs.Length == 1
                      let parameters = method.GetParameters()
                      where parameters.Length == 1
                      where parameters[0].ParameterType == 
                            typeof(Func<>).MakeGenericType(typeArgs[0])
                      select method;

        Console.WriteLine("Matching methods...");
        foreach (var method in methods)
        {
            Console.WriteLine(method);
        }
    }
}

Basically generics and reflection are really nasty in combination, I'm afraid :(