C#解除文件锁定

public static void StreamsFile(string fi)
        {
                try
                {
                    var p = new Process
                    {
                        StartInfo =
                        {
                            FileName = Environment.CurrentDirectory + "\\streams64.exe",
                            UseShellExecute = false,
                            Arguments = " -d \""+fi+"\""
                        }
                    };

                    //执行参数
                    p.StartInfo.UseShellExecute = false;  ////不使用系统外壳程序启动进程
                    p.StartInfo.CreateNoWindow = true;  //不显示dos程序窗口
                    p.StartInfo.RedirectStandardInput = true;
                    p.StartInfo.RedirectStandardOutput = true;
                    p.StartInfo.RedirectStandardError = true;//把外部程序错误输出写到StandardError流中
                    p.ErrorDataReceived += new DataReceivedEventHandler(p_ErrorDataReceived);
                    p.OutputDataReceived += new DataReceivedEventHandler(p_OutputDataReceived);
                    p.StartInfo.UseShellExecute = false;
                    p.Start();
                    p.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
                    p.BeginErrorReadLine();//开始异步读取
                    p.WaitForExit();//阻塞等待进程结束
                    p.Close();//关闭进程
                    p.Dispose();//释放资源

                }
                catch (Exception e)
                {
                    Console.WriteLine(e.ToString());
                }
            }

            public static void p_ErrorDataReceived(object sender, DataReceivedEventArgs e)
            {
                Console.WriteLine(e.Data);
            }
            public static void p_OutputDataReceived(object sender, DataReceivedEventArgs e)
            {
                Console.WriteLine(e.Data);
            }