ＤＥＢＵＧ出错，请大家指点，我刚刚开始学，什么都不懂，请大家帮帮我

在ＷＯＲＤ里添加插件，reference里加了
System.Windows.Forms,
System.Drawing,
System.XML,
Microsoft Word 11.0 Object Library
然后修改Ｃonnect.cs的一些函数

namespace AK47
{
    using System;
    using Extensibility;
    using System.Runtime.InteropServices;
中间省略

           public void OnStartupComplete(ref System.Array custom)
        {
            MessageBox.Show(wordApp.ActiveDocument.Name);
        }

省略
}
debug的结果是------ 已启动生成: 项目: AK47, 配置: Debug Any CPU ------
C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\Csc.exe /noconfig /nowarn:1701,1702 /warn:4 /define:DEBUG;TRACE /reference:"C:\Program Files\Common Files\Microsoft Shared\MSEnv\PublicAssemblies\Extensibility.dll" /reference:C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Data.dll /reference:C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.dll /reference:C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Drawing.dll /reference:C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.Windows.Forms.dll /reference:C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727\System.XML.dll /reference:obj\Debug\Interop.Microsoft.Office.Core.dll /reference:obj\Debug\Interop.VBIDE.dll /reference:obj\Debug\Interop.Word.dll /debug+ /optimize- /out:obj\Debug\AK47.dll /target:library AssemblyInfo.cs Connect.cs
e:\My project\lj\AK47\AK47\Connect.cs(106,13): 错误 CS0103: 当前上下文中不存在名称“MessageBox”

编译完成 -- 1 个错误，0 个警告
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