using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        var types = new Type[]

        {

            typeof(String),

            typeof(Int32),

            typeof(DateTime)

        };

        ArrayParam(types);

        EnumParam(types);

    }

    private static void ArrayParam(Type[] types)

    {

        Console.WriteLine("ArrayParam OK");

    }

​

    private static void EnumParam(IEnumerable<Type> types)

    {

        Console.WriteLine("EnumParam OK");

    }

}