ASP.NET错误处理

using System;
using System.Web;

namespace Water.Basis
{
    public class ErrorLog
    {
        static ErrorLog() { }

        #region WriteEntry

        public static void WriteEntry()
        {
            Exception erroy = HttpContext.Current.Server.GetLastError().GetBaseException();
            string path = HttpContext.Current.Request.PhysicalApplicationPath;
            string logDir = path + "Log\\";
            string LogFile = logDir + DateTime.Now.ToString("yyyy-MM-dd") + ".log";
            if (!System.IO.Directory.Exists(logDir))
            {
                System.IO.Directory.CreateDirectory(logDir);
            }
            System.IO.StreamWriter sw;
            if (System.IO.File.Exists(LogFile))
            {
                sw = System.IO.File.AppendText(LogFile);
            }
            else
            {
                sw = System.IO.File.CreateText(LogFile);
            }
            sw.WriteLine("出错页面是：" + HttpContext.Current.Request.Url.ToString());
            sw.WriteLine("异常信息：" + erroy.Message);
            sw.WriteLine("Source：" + erroy.Source);
            sw.WriteLine("StackTrace：" + erroy.StackTrace);
            sw.WriteLine("发生时间：" + DateTime.Now.ToString());
            sw.WriteLine();
            sw.WriteLine("**********************************************************************************");
            sw.WriteLine();
            sw.Close();
            HttpContext.Current.Server.ClearError();
        }

        #endregion
    }
}