1.發生未處理異常是CLR行為控制
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework的DbgJITDebugLaunchSetting
0 顯示對話框詢問用戶是否要調試。
1 不向用戶顯示任何對話框，調用MgdUEPolicy回調方法。
2 不向用戶顯示任何對話框，CLR啟動調試器并將其連接到應用程序上。

using System;
using System.Diagnostics;
using System.Windows.Forms;
namespace TestExce
{
	
	/// <summary>
	/// 未處理異常的策略
	/// </summary>
	class Class1
	{

		[STAThread]
		static void Main(string[] args)
		{
			AppDomain.CurrentDomain.UnhandledException+=new UnhandledExceptionEventHandler(MgdUEPolicy);
			try
			{
				Object o=null;
				o.GetType();
			}
			finally
			{
				Console.WriteLine("In finally");
			}
		}
		static void MgdUEPolicy(Object sender,UnhandledExceptionEventArgs e)
		{
			String info;
			Exception ex=e.ExceptionObject as Exception;
			if(ex!=null)
			{
				//CLS兼容異常
				info=ex.ToString();
			}
			else
			{
				//CLS不兼容異常
				info=String.Format("Non-CLS-Compliant exception:Type={0},String={1}",e.ExceptionObject.GetType(),e.ExceptionObject.ToString());
			}
#if DEBUG
			if(!e.IsTerminating)
			{
				Debugger.Launch();
			}
			else
			{
				Debugger.Launch();
			}
#else
			if(!e.IsTerminating)
			{
				
			}
			else
			{
				String msg=String.Format("{0} has encountered aproblem and "+
					"need to close.we are sorry for the inconvenience.\n\n"+
					"Please tell{1} about this problem.\n"+
					"We have created an error report that you can send to"+
					"help us imporove{0}."+
					"We will treat this report as confidential and anonymuse.\n\n"+
					"Would you like to send the report?","(AppName)","(CompanyName)");
				if(MessageBox.Show(msg,"(AppName)",MessageBoxButtons.YesNo)==DialogResult.Yes)
				{
					MessageBox.Show(info,"Error Report");
				}
			}		
#endif

		}
	}
}