C# 如何重定向控制台程序';以线程安全的方式输出到文本框?
我无法将控制台输出重定向到windows窗体文本框。这个问题与线程有关。我正在以以下方式运行控制台应用程序C# 如何重定向控制台程序';以线程安全的方式输出到文本框?,c#,multithreading,winforms,textbox,console-application,C#,Multithreading,Winforms,Textbox,Console Application,我无法将控制台输出重定向到windows窗体文本框。这个问题与线程有关。我正在以以下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;
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并处理数据
// 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,控制台文本如下所示追加
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);
}
}
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();
}
从我看到的所有文档和示例来看,这似乎是正确的方法,只是调用out_txtbx.Invoke时它会使应用程序崩溃
有什么可能被打破,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) 问题是,由于这条线路,应用程序陷入了“致命的拥抱”状态
proc.WaitForExit();
应该删除该行,方法应该如下所示
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);
}
}
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();
}
并且应该提供一个事件处理程序
/// <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();
}
//
///控制台进程完成时要采取的操作
///
私有void进程退出(对象发送方,System.EventArgs e)
{
进程进程=(进程)发送方;
//请稍等片刻,以允许处理和附加所有控制台输出
//在附加成功/失败消息之前。
睡眠(40);
if(proc.ExitCode==0)
{
这个.AppendText(“Success.+Environment.NewLine”);
ExitBootloader();
}
其他的
{
这个.AppendText(“Failed.+Environment.NewLine”);
}
过程关闭();
}
试试看
这叫做死锁。主线程被阻塞,正在等待进程退出。这使它无法履行基本职责。比如保持用户界面的更新。并确保调度Control.Invoke()请求。这将阻止AppendText()方法完成。这将停止退出的过程。这会阻止UI线程通过WaitForExit()调用。“致命的拥抱”,又名死锁
不能阻止主线程。改用Process.Exited事件。我这样做没有错误。如果在我拿到代码样本的时候还没有一个足够的答案,我会发布。请注意,这将是今晚晚些时候我回家的时候。我创建了一个TextWriter对象,该对象写入文本框,然后将Console.SetOut指向TextWriter。请参阅@decyclone:他说它在调用out_txtbx.Invoke的那一行。@SLaks没有错误,当我运行它或尝试跨入/越过out_txtbx.Invoke行时,应用程序只是挂起。Visual C#在调试时似乎不提供暂停(仅在断点上暂停),因此我不知道调用之后会发生什么。主Winforms线程是否正在忙于执行其他操作?单击调试工具栏上的暂停按钮,或在VS中按Ctrl+pause。