System.Diagnostics.Process程序繼續運行

Question

我試圖從命令行應用程序中使用ffmpeg庫將一些avi文件轉換爲mkv。我做了一個方法，可以讓我做到這一點：

public bool convertAvitoMkv(string path, string sourceName, string destName) 
    { 

     bool returncode = false; 
     try 
     { 
      string comando = string.Format("-i {0} -c:v libx264 -crf 19 -preset slow -c:a libfaac -b:a 192k -ac 2 {1}", string.Format("{0}\\{1}",path,sourceName), string.Format("{0}\\{1}",path,destName) + ".mkv"); 
      System.Diagnostics.Process process = new System.Diagnostics.Process(); 
      System.Diagnostics.ProcessStartInfo startInfo = new System.Diagnostics.ProcessStartInfo(); 
      startInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden; 
      startInfo.FileName = "ffmpeg.exe"; 
      startInfo.WorkingDirectory = programPath; 
      startInfo.CreateNoWindow = true; 
      startInfo.Arguments = comando; 
      process.StartInfo = startInfo; 
      process.Start(); 
      while (!process.HasExited) 
      { 
       process.Kill(); 
       //continue hasta que termine la ejecucion 
      } 

      returncode = process.HasExited; 
     } 
     catch (Exception ex) 
     { 

     } 
     return returncode; 
    } 

以前的版本沒有的，而（！process.HasExited），但我說，因爲我注意到，有很多的ffmpeg的實例。 EXE運行，我不得不手動關閉。我如何保證每次轉換都已完成，並且ffmpeg的每個實例都已關閉？ 關於

Answer 1

public bool concatenarArchivos(string archivos, string path, string destName) 
    { 
     bool returncode = false; 
     try 
     { 
      string[] extensions = {".mp4"}; 
      string[] dirContents = System.IO.Directory.GetFiles(path, "*.*").Where(f => extensions.Contains(new FileInfo(f).Extension.ToLower())).ToArray(); 
      if (dirContents.Length > 0) 
      { 
       string comando = string.Format("-f concat -i {0} -c copy {1}", archivos, string.Format("{0}\\{1}", path, destName)); 
       System.Diagnostics.Process process = new System.Diagnostics.Process(); 
       System.Diagnostics.ProcessStartInfo startInfo = new System.Diagnostics.ProcessStartInfo(); 
       startInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden; 
       startInfo.FileName = "ffmpeg.exe"; 
       startInfo.WorkingDirectory = programPath; 
       startInfo.CreateNoWindow = true; 
       startInfo.Arguments = comando; 
       process.StartInfo = startInfo; 
       process.Start(); 
       process.WaitForExit(); 
       //process.Close(); 
       process.Dispose(); 
       //returncode = process.HasExited; 
      } 
     } 
     catch (Exception ex) 
     { 

     } 
     return returncode; 
    } 

Answer 2

我有同樣的問題。在調試時，我注意到當我使用WaitForExit時，它一直等待無限期。當我使用!process.HasExited的while循環時，它也沒有通過while循環。

只要我爲標準輸出和錯誤添加了重定向，並且讀取它開始按照預期工作的流。

看來，當有某種輸出（常規和/或錯誤）時，進程會一直等待，直到輸出處理完畢。在它不會退出之前。

如下更改您的代碼很可能會解決您的問題。

public bool convertAvitoMkv(string path, string sourceName, string destName) 
    { 

     bool returncode = false; 
     try 
     { 
      string comando = string.Format("-i {0} -c:v libx264 -crf 19 -preset slow -c:a libfaac -b:a 192k -ac 2 {1}", string.Format("{0}\\{1}",path,sourceName), string.Format("{0}\\{1}",path,destName) + ".mkv"); 
      System.Diagnostics.Process process = new System.Diagnostics.Process(); 
      System.Diagnostics.ProcessStartInfo startInfo = new System.Diagnostics.ProcessStartInfo(); 
      startInfo.WindowStyle = System.Diagnostics.ProcessWindowStyle.Hidden; 
      startInfo.FileName = "ffmpeg.exe"; 
      startInfo.WorkingDirectory = programPath; 
      startInfo.CreateNoWindow = true; 
      startInfo.Arguments = comando; 
      startInfo.RedirectStandardOutput = true; 
      startInfo.RedirectStandardError = true; 
      process.StartInfo = startInfo; 
      process.Start(); 

      StreamReader readerOut = process.StandardOutput; 
      StreamReader readerErr = process.StandardError; 
      // Process the readers e.g. like follows 
      string errors = readerErr.ReadToEnd(); 
      string output = readerOut.ReadToEnd(); 

      while (!process.HasExited) 
      { 
       continue; 
      } 

      returncode = process.HasExited; 
     } 
     catch (Exception ex) 
     { 

     } 
     return returncode; 
    }