我无法将控制台输出重定向到
Windows窗体文本框.问题与线程有关.我正在以下列方式运行控制台应用程序,
private void RunConsoleApp() { Process proc = new Process(); proc.StartInfo.FileName = "app.exe"; proc.StartInfo.Arguments = "-a -b -c"; proc.StartInfo.UseShellExecute = false; // set up output redirection proc.StartInfo.RedirectStandardOutput = true; proc.StartInfo.RedirectStandardError = true; proc.EnableRaisingEvents = true; proc.StartInfo.CreateNoWindow = true; // Set the data received handlers proc.ErrorDataReceived += proc_DataReceived; proc.OutputDataReceived += proc_DataReceived; proc.Start(); proc.BeginErrorReadLine(); proc.BeginOutputReadLine(); proc.WaitForExit(); if (proc.ExitCode == 0) { out_txtbx.AppendText("Success." + Environment.NewLine); } else { out_txtbx.AppendText("Failed." + Environment.NewLine); } }
然后使用此输出处理程序捕获和处理数据,
// Handle the date received by the console process void proc_DataReceived(object sender,DataReceivedEventArgs e) { if (e.Data != null) { if ((e.Data.EndsWith("DONE.")) || (e.Data.EndsWith("Failed.")) || (e.Data.StartsWith("RESET"))) { // This crashes the application,but is supposedly the correct method this.AppendText(e.Data + Environment.NewLine); // This works,but the debugger keeps warning me that the call // is not thread safe //out_txtbx.AppendText(e.Data + Environment.NewLine); } } }
然后像这样追加控制台文本,
delegate void AppendTextDelegate(string text); // Thread-safe method of appending text to the console Box private void AppendText(string text) { // Use a delegate if called from a different thread,// else just append the text directly if (this.out_txtbx.Invokerequired) { // Application crashes when this line is executed out_txtbx.Invoke(new AppendTextDelegate(this.AppendText),new object[] { text }); } else { this.out_txtbx.AppendText(text); } }
从我看到的所有文档和示例看来,这似乎是正确的方法,除了它在调用out_txtbx.Invoke时崩溃应用程序.
什么可以被打破,有什么替代方法可以做到这一点?
解决方案(正如Hans Passant所指出的那样)
问题是该应用程序由于线路而陷入“致命的拥抱”,
proc.WaitForExit();
private void RunConsoleApp() { Process proc = new Process(); proc.StartInfo.FileName = "app.exe"; proc.StartInfo.Arguments = "-a -b -c"; proc.StartInfo.UseShellExecute = false; // set up output redirection proc.StartInfo.RedirectStandardOutput = true; proc.StartInfo.RedirectStandardError = true; proc.EnableRaisingEvents = true; proc.StartInfo.CreateNoWindow = true; // Set the data received handlers proc.ErrorDataReceived += proc_DataReceived; proc.OutputDataReceived += proc_DataReceived; // Configure the process exited event proc.Exited += new EventHandler(ProcExited); proc.Start(); proc.BeginErrorReadLine(); proc.BeginOutputReadLine(); // This blocks the main thread and results in "deadly embrace" // The Process.Exited event should be used to avoid this. //proc.WaitForExit(); }
并应提供事件处理程序,
/// <summary> /// Actions to take when console process completes /// </summary> private void ProcExited(object sender,System.EventArgs e) { Process proc = (Process)sender; // Wait a short while to allow all console output to be processed and appended // before appending the success/fail message. Thread.Sleep(40); if (proc.ExitCode == 0) { this.AppendText("Success." + Environment.NewLine); ExitBootloader(); } else { this.AppendText("Failed." + Environment.NewLine); } proc.Close(); }