.net中捕捉全局未处理异常的三种方式示例

protected void Page_Error(object sender, EventArgs e)
  {
   string errorMsg = String.Empty;
   Exception currentError = Server.GetLastError();
   errorMsg += "来自页面的异常处理<br />";
   errorMsg += "系统发生错误:<br />";
   errorMsg += "错误地址:" + Request.Url + "<br />";
   errorMsg += "错误信息:" + currentError.Message + "<br />";
   Response.Write(errorMsg);
   Server.ClearError();//清除异常(否则将引发全局的Application_Error事件)
  }

/// <summary>
 /// MyHttpModule
 /// </summary>
 public class MyHttpModules : IHttpModule
 {
　　　　　public void Init(HttpApplication context)
  {
   context.Error += new EventHandler(context_Error);
  }

  public void context_Error(object sender, EventArgs e)
  {
   //此处处理异常
   HttpContext ctx = HttpContext.Current;
   HttpResponse response = ctx.Response;
   HttpRequest request = ctx.Request;

   //获取到HttpUnhandledException异常，这个异常包含一个实际出现的异常
   Exception ex = ctx.Server.GetLastError();
   //实际发生的异常
   Exception iex = ex.InnerException;

   response.Write("来自ErrorModule的错误处理<br />");
   response.Write(iex.Message);

   ctx.Server.ClearError();
  }
}

<httpModules>
　　<add name="MyHttpModule" type="MyHttpModule.MyHttpModules,MyHttpModule" />
</httpModules>

<modules>
　　<add name="MyHttpModule" type="MyHttpModule.MyHttpModules,MyHttpModule"/>
</modules>

void Application_Error(object sender, EventArgs e)
  {
   //获取到HttpUnhandledException异常，这个异常包含一个实际出现的异常
   Exception ex = Server.GetLastError();
   //实际发生的异常
   Exception iex = ex.InnerException;

   string errorMsg = String.Empty;
   string particular = String.Empty;
   if (iex != null)
   {
    errorMsg = iex.Message;
    particular = iex.StackTrace;
   }
   else
   {
    errorMsg = ex.Message;
    particular = ex.StackTrace;
   }
   HttpContext.Current.Response.Write("来自Global的错误处理<br />");
   HttpContext.Current.Response.Write(errorMsg);

   Server.ClearError();//处理完及时清理异常
  }