c# - 如何在WPF应用程序上修复 “The calling thread cannot access this object because a different thread owns it.”

Question

我有以下WPF代码，它在“TextBox t = tabItem.Content as TextBox;”处给了我一个异常(exception)。错误显示“调用线程无法访问该对象，因为其他线程拥有它”。如何解决该异常？

问候!

private void btnAdd_Click(object sender, RoutedEventArgs e)
{
  RichTextBox statusRichTextBox = new RichTextBox();
  CloseableTabItem tabItem = new CloseableTabItem();
  tabItem.Content = statusRichTextBox;
  tabItem.Header = "New Tab";
  MainTab.Items.Add(tabItem);
  Thread t = new Thread(new ParameterizedThreadStart(worker));
  t.Start(tabItem); 
}


public void worker(object threadParam)
{
  CloseableTabItem tabItem = (CloseableTabItem)threadParam;

  TextBox t = tabItem.Content as TextBox; //exception here
  if (t != null)
    Window1.myWindow1.Dispatcher.BeginInvoke((Action)(() => { t.Text = "THIS IS THE TEXT"; }), System.Windows.Threading.DispatcherPriority.Normal);
}

Answer 1

UI对象的属性和方法只能在创建这些对象的线程上访问，因此，当您尝试在辅助线程上访问tabItem.Content时，它将失败。

您可以改为:

TextBox t;
Window1.myWindow1.Dispatcher.Invoke(new Action(() => t = tabItem.Content as TextBox));