/// 读  public void inint()        {            FileStream fs = new FileStream("D:/123.txt",FileMode.Open,FileAccess.Read );            StreamReader sr = new StreamReader(fs);            sr.BaseStream.Seek(0, SeekOrigin.Begin);            string str = sr.ReadToEnd();            if (str!="")            {                Console.WriteLine("{0}", str);                str = sr.ReadLine();            }            sr.Close();            fs.Close();        }///写入            using (StreamWriter sw=File.AppendText("D:/123.txt"))            {                sw.Write("我爱你中国");                sw.Dispose();            }