Use Process.OutputDataReceived event from the process, to recieve the data you need.
Example:
var myProc= new Process();
...
myProc.StartInfo.RedirectStandardOutput = true;
myProc.OutputDataReceived += new DataReceivedEventHandler(MyProcOutputHandler);
...
private static void MyProcOutputHandler(object sendingProcess,
DataReceivedEventArgs outLine)
{
// Collect the sort command output.
if (!String.IsNullOrEmpty(outLine.Data))
{
....
}
}