LowLevel Part 1

Program.cs

using System;
using System.Reflection.Emit;


class Program
{
    public delegate int Add_dt(int a, int b, int c);
    public static int Add(int a, int b, int c)
    {
        return a + b + c;
    }
    static void Main(string[] args)
    {
        var method = new DynamicMethod("CustomAdd", typeof(int), new[] { typeof(int), typeof(int), typeof(int) });
        var il = method.GetILGenerator();

        il.Emit(OpCodes.Ldarg_0);     // Load A Parameter
        il.Emit(OpCodes.Ldarg_1);     // Load B Parameter
        il.Emit(OpCodes.Add);          // Pop both two parameters above off the stack and add the result to the stack!
        il.Emit(OpCodes.Ldarg_2);      // Load C Parameter
        il.Emit(OpCodes.Add);          // Add up both the Result of A + B and C together
        il.Emit(OpCodes.Ret);          // Return the result!
    // We need to use a delegate type so we can cast our Delegate to the function type we want!
        var customAdd = (Add_dt)method.CreateDelegate(typeof(Add_dt));

        int a = 44, b = 55, c = 66;
        Console.WriteLine("Compiled Add Method:");
        Console.WriteLine("{0} + {1} + {2} = {3}", a, b, c, Add(a, b, c));
        Console.WriteLine("Runtime Emitted Add Method:");
        Console.WriteLine("{0} + {1} + {2} = {3}", a, b, c, customAdd(a, b, c));
        Console.ReadLine();
    }
}