using System;

using System.Collections.Generic;

using System.Text;

using System.Runtime.InteropServices;

namespace Example03

{

    class Program

    {

        //注意DllImport是一个Attribute Property，在System.Runtime.InteropServices命名空间中定义

        //extern与DllImport一起使用时必须再加上一个static修饰符

        [DllImport("User32.dll")]

        public static extern int MessageBox(int Handle, string Message, string Caption, int Type);

        static int Main()

        {

            string myString;

            Console.Write("Enter your message: ");

            myString = Console.ReadLine();

            return MessageBox(0, myString, "My Message Box", 0);

        }

    }

}