exp.exe命令未完成。它正在显示正在进行中

Question

private void RunExportCommand()
    {            
        try
        {
            appLogger.WriteLog("RunExportCommand Method.");
            appLogger.WriteLog("Starting exporting data to dump file.");
            using (Process processExp = new Process())
            {
                string fileName = "exp.exe";
                processExp.StartInfo.FileName = fileName;                   
                processExp.StartInfo.Arguments = GetCommandString();                  
                processExp.StartInfo.CreateNoWindow = true;
                processExp.StartInfo.UseShellExecute = false;
                processExp.StartInfo.RedirectStandardError = true;
                processExp.StartInfo.RedirectStandardOutput = false;
                processExp.StartInfo.RedirectStandardInput = true;
                appLogger.WriteLog("Before Start");
                processExp.Start();
                appLogger.WriteLog("After Start");
                appLogger.WriteLog("Started exporting data to dump file.");
                processExp.StandardInput.AutoFlush = true;                 
                processExp.StandardInput.Close();
                appLogger.WriteLog("Before WaitForExit");
               processExp.WaitForExit(Int32.MaxValue);
                appLogger.WriteLog("After WaitForExit");
            }
            appLogger.WriteLog("Successfully exported data to dump file.");
        }
        catch (Exception e)
        {
            appLogger.WriteLog("Exception while exporting data. " + e.ToString());
            throw new Exception("Exception while exporting data.", e);
        }
    }

在此代码processExp.WaitForExit(Int32.MaxValue)行中没有执行，但在该文件行工作之前。如果我使用创建的filename.txt(log)来复制或移动，则会显示舔错误

＆＃34; IsErrorOccurred System.IO.IOException发生错误：进程无法访问文件＆＃39; C：MyBKP \ BAK_01_01062017.txt＆＃39;因为它正被另一个进程使用。＆＃34;