C# Code:

//运行cmd
Process p = new Process();
p.StartInfo.FileName = txtProgramPath.Text + "\\ffmpeg.exe";
p.StartInfo.UseShellExecute = false;
p.StartInfo.Arguments = string.Format("-i {0} -b:v {1} -bufsize {2} -vf \"scale = {3}, setsar = 1\" -profile:v baseline -level {4} -pix_fmt yuv420p {5}",
sourceFile, txtRate.Text, txtRate.Text, txtScale.Text, txtLevel.Text, destFile) + " ";

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.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

//来源:C/S框架网(www.csframework.com) QQ:23404761