FileStream Close

            FileStream f = new FileStream("hou.txt",FileMode.Create,FileAccess.ReadWrite);
            StreamWriter wf = new StreamWriter(f);
            wf.Write("Hello world!");
            wf.Close();
            f.Close(); 

 

 

不要忘记最后两句,否则数据只是在缓冲区中,而没有写入文件.