通過Process.Start（startInfo）在另一個進程上出現異常行爲 - 繼續

Question

原始位置（strange behaviour on another process via Process.Start(startInfo)）不允許我正確地發佈測試代碼。我必須在這裏開始一個新的問題。

我們的C＃（V3.5）需要調用C++可執行文件來處理原始數據文件併爲我們生成結果文件。

它用下面的代碼工作之前（不含ReadToEnd的（）或的ReadLine（）調用）：

startInfo.UseShellExecute = false; 
startInfo.RedirectStandardError = true; 
startInfo.RedirectStandardOutput = true; 

現在輸入原始數據文件改變（大於之前）。我們對該可執行文件的調用將永遠掛起。根據建議，我添加了ReadToEnd（）或ReadLine（），但它會掛在這些調用上。所以我必須要麼使用startInfo.UseShellExecute = true;要麼使用

startInfo.UseShellExecute = false; 
// and with 
startInfo.RedirectStandardError = false; 
startInfo.RedirectStandardOutput = false; 

不知道爲什麼？

以下是情況下，我測試：

1. 工作情況：

   ProcessStartInfo startInfo = new ProcessStartInfo(); 
   startInfo.CreateNoWindow = true; 
   startInfo.UseShellExecute = false; 
   startInfo.RedirectStandardError = false; 
   startInfo.RedirectStandardOutput = false; 
   startInfo.WindowStyle = ProcessWindowStyle.Hidden; 
   startInfo.FileName = path; 
   startInfo.Arguments = rawDataFileName; 
   //startInfo.WorkingDirectory = Util.GetParentDirectory(path, 1); 
   try 
   { 
       Process correctionProcess = Process.Start(startInfo); 
       correctionProcess.WaitForExit(); 
   } 
   

2. 工作情況：

   ProcessStartInfo startInfo = new ProcessStartInfo(); 
   startInfo.CreateNoWindow = true; 
   startInfo.UseShellExecute = true; 
   startInfo.RedirectStandardError = false;//can be commented out 
   startInfo.RedirectStandardOutput = false;//can be commented out 
   startInfo.WindowStyle = ProcessWindowStyle.Hidden; 
   startInfo.FileName = path; 
   startInfo.Arguments = rawDataFileName; 
   startInfo.WorkingDirectory = Util.GetParentDirectory(path, 1); 
   try 
   { 
       Process correctionProcess = Process.Start(startInfo); 
       correctionProcess.WaitForExit(); 
   } 
   

3. 不工作的情況下（使用ReadLine()）：

   ProcessStartInfo startInfo = new ProcessStartInfo(); 
   startInfo.CreateNoWindow = true; 
   startInfo.UseShellExecute = false; 
   startInfo.RedirectStandardError = true; 
   startInfo.RedirectStandardOutput = true; 
   startInfo.WindowStyle = ProcessWindowStyle.Hidden; 
   startInfo.FileName = path; 
   startInfo.Arguments = rawDataFileName; 
   //startInfo.WorkingDirectory = Util.GetParentDirectory(path, 1); 
   try 
   { 
       Process correctionProcess = Process.Start(startInfo); 
       while (!correctionProcess.HasExited) 
       { 
        Log.logItem(LogType.Performance, "read errorMsg @@@@", "DPTM::correctData()", ""); 
        string errorMsg = correctionProcess.StandardError.ReadLine(); // <-- Hangs here 
        Log.logItem(LogType.Performance, "read errorMsg", "DPTM::correctData()", "errorMsg=" + errorMsg); 
        string outputMsg = correctionProcess.StandardOutput.ReadLine(); 
        Log.logItem(LogType.Performance, "read outputMsg", "DPTM::correctData()", "outputMsg=" + outputMsg); 
        Thread.Sleep(100); 
       } 
   } 
   

4. 不工作的情況下（使用ReadToEnd()）：

   ProcessStartInfo startInfo = new ProcessStartInfo(); 
   startInfo.CreateNoWindow = true; 
   startInfo.UseShellExecute = false; 
   startInfo.RedirectStandardError = true; 
   startInfo.RedirectStandardOutput = true; 
   startInfo.WindowStyle = ProcessWindowStyle.Hidden; 
   startInfo.FileName = path; 
   startInfo.Arguments = rawDataFileName; 
   //startInfo.WorkingDirectory = Util.GetParentDirectory(path, 1); 
   try 
   { 
       Process correctionProcess = Process.Start(startInfo); 
       while (!correctionProcess.HasExited) 
       { 
        Log.logItem(LogType.Performance, "read errorMsg @@@@", "DPTM::correctData()", ""); 
        string errorMsg = correctionProcess.StandardError.ReadToEnd(); // <-- Hangs here! 
        Log.logItem(LogType.Performance, "read errorMsg", "DPTM::correctData()", "errorMsg=" + errorMsg); 
        string outputMsg = correctionProcess.StandardOutput.ReadToEnd(); 
        Log.logItem(LogType.Performance, "read outputMsg", "DPTM::correctData()", "outputMsg=" + outputMsg); 
        Thread.Sleep(100); 
       } 
   } 
   

5. 不工作的情況下：

   ProcessStartInfo startInfo = new ProcessStartInfo(); 
   startInfo.CreateNoWindow = true; 
   startInfo.UseShellExecute = false; 
   startInfo.RedirectStandardError = true; 
   startInfo.RedirectStandardOutput = true; 
   startInfo.WindowStyle = ProcessWindowStyle.Hidden; 
   startInfo.FileName = path; 
   startInfo.Arguments = rawDataFileName; 
   //startInfo.WorkingDirectory = Util.GetParentDirectory(path, 1); 
   try 
   { 
       Process correctionProcess = Process.Start(startInfo); 
       Log.logItem(LogType.Performance, "read errorMsg @@@@", "DPTM::correctData()", ""); 
       string errorMsg = correctionProcess.StandardError.ReadToEnd(); // <-- Hangs here! 
       Log.logItem(LogType.Performance, "read errorMsg", "DPTM::correctData()", "errorMsg=" + errorMsg); 
       string outputMsg = correctionProcess.StandardOutput.ReadToEnd(); 
       Log.logItem(LogType.Performance, "read outputMsg", "DPTM::correctData()", "outputMsg=" + outputMsg); 
       correctionProcess.WaitForExit(); 
   } 
   

Answer 1

你在錯誤/輸出緩衝陷入僵局。您的第二個進程正在等待緩衝區在您等待該進程完成時釋放。您需要異步讀取輸出/錯誤流以防止出現這種情況。

看看你的MSDN示例：哇，這個示例真的讓人困惑......如果他們僅僅將它限制在標準輸出或std錯誤，它會更容易遵循。

您需要先設置數據處理程序

correctionProcess.OutputDataReceived += new DataReceivedEventHandler(OutputDataHandler); 

，然後調用

p.BeginOutputReadLine(); 

就像評論[容易混淆]建議做任何嘗試讀取輸出那裏。改用處理程序。

private void OutputDataHandler(object sendingProcess, DataReceivedEventArgs data) 
    { 
     if (data.Data != null) 
     { 
      // append data.Data to your internal buffer (StringBuilder?) 
     } 
    }