写操作xml文件，进程和线程同时写

            Mutex WriteMutex = new Mutex(false, "Write");
            WriteMutex.WaitOne();
            DateTime dttime = System.DateTime.Now;
            Response.Write(dttime);
            int i = 0;
            lock (this)
            {
                 while (System.DateTime.Now<dttime.AddSeconds(5))
                 {
                     XmlDocument domtest = new XmlDocument();
                     domtest.Load(@"201012.xml");
                     XmlElement test = domtest.CreateElement("test");
                     i = i + 1;
                     test.SetAttribute("datetime", i.ToString());
                     domtest.DocumentElement.AppendChild(test);
                     domtest.Save(@"201012.xml");
                 }
            }
            WriteMutex.ReleaseMutex();

            Response.Write("<br/>"+Base.GetNowTime());
            return;