1.第一种做法，在Web.config文件配置

<system.web>
      <customErrors defaultRedirect="~/ErrorPage.aspx"
                     mode="RemoteOnly">
      </customErrors>
</system.web>

 

  defaultRedirect属性用来指明当aspx页面发生了未处理错误时导向的页面; 但Asp.net使用重定向机制来重新导航错误页面，这样错误信息就会丢失，也就是说我们用Server.GetLastError()获得的Exception对象始终是空的。虽然可以提示用户出错，并提供一个返回出错页面的链接，却不能给管理员一个很好的错误提示。

2.第二种做法：在global文件里的Application_Error方法中处理

代码
protected void Application_Error(Object sender, EventArgs e)
        {
            Exception ex=Server.GetLastError().GetBaseException();

            string errorTime="发生时间："+DateTime.Now.ToString();
            string errorAddress="发生异常页："+Request.Url.ToString();
            string errorInfo="异常信息："+ex.Message;
            string errorSource="错误源："+ex.Source;
            string errorTrace="堆栈信息："+ex.StackTrace;
            Server.ClearError();

            System.IO.StreamWriter writer=null;
            try
            {
                lock(this)
                {
                    //写入日志
                    string year=DateTime.Now.Year.ToString();
                    string month=DateTime.Now.Month.ToString();
                    string day=DateTime.Now.Day.ToString();
                    string path=string.Empty;
                    string filename=DateTime.Now.ToString("yyyyMMdd")+".txt";
                    path=Server.MapPath("~/Error/")+year+month+day;
                    if(!Directory.Exists(path))
                    {
                        Directory.CreateDirectory(path);
                    }
                    System.IO.FileInfo file=new FileInfo(path+"/"+filename);
                    writer=new StreamWriter(file.FullName,true);//文件不在则创建，true表示追加
                    writer.WriteLine("用户IP:"+Request.UserHostAddress);
                    writer.WriteLine(errorTime);
                    writer.WriteLine(errorAddress);
                    writer.WriteLine(errorInfo);
                    writer.WriteLine(errorSource);
                    writer.WriteLine(errorTrace);
                    writer.WriteLine("-------------------------------------------------------");

                }
            }
            finally
            {
                if(writer!=null)
                {
                    writer.Close();
                }
            }
            Server.Transfer("~/ErrorPage.aspx"); //跳转到显示友好错误的页面

        }

然后在ErrorPage.aspx页面显示一些好友的提示信息.

3.第三种做法：在Page_Error事件里面处理

代码
        private void Page_Load(object sender, System.EventArgs e)
        {
            throw(new ArgumentNullException());
        }

        public void Page_Error(object sender,EventArgs e)
        {
            Exception ex=Server.GetLastError().GetBaseException();

            string errorTime="发生时间："+DateTime.Now.ToString();
            string errorAddress="发生异常页："+Request.Url.ToString();
            string errorInfo="异常信息："+ex.Message;
            string errorSource="错误源："+ex.Source;
            string errorTrace="堆栈信息："+ex.StackTrace;

            Server.ClearError();

            System.IO.StreamWriter writer=null;
            try
            {
                lock(this)
                {
                    //写入日志
                    string year=DateTime.Now.Year.ToString();
                    string month=DateTime.Now.Month.ToString();
                    string day=DateTime.Now.Day.ToString();
                    string path=string.Empty;
                    string filename=DateTime.Now.ToString("yyyyMMdd")+".txt";
                    path=Server.MapPath("~/Error/")+year+month+day;
                    if(!Directory.Exists(path))
                    {
                        Directory.CreateDirectory(path);
                    }
                    System.IO.FileInfo file=new FileInfo(path+"/"+filename);
                    writer=new StreamWriter(file.FullName,true);//文件不在则创建，true表示追加
                    writer.WriteLine("用户IP:"+Request.UserHostAddress);
                    writer.WriteLine(errorTime);
                    writer.WriteLine(errorAddress);
                    writer.WriteLine(errorInfo);
                    writer.WriteLine(errorSource);
                    writer.WriteLine(errorTrace);
                    writer.WriteLine("-------------------------------------------");

                }
            }
            finally
            {
                if(writer!=null)
                {
                    writer.Close();
                }
            }

            Server.ClearError();//防止错误继续到要被处理的 Application_Error 事件中。
            Response.Redirect("~/ErrorPage.aspx");
           
        }
 

经常的做法是使用第二种方法，然后再写一个发送短信的方法（调用移动的短信借口），这样的话程序出错的时候，管理员可以收到程序出错的信息。