Update a TextBox from another thread in WPF

Asked Mar 14 '20 at 13:22

Active Mar 14 '20 at 13:22

Viewed 35 times

I want to update a TextBox from another thread in a WPF application. Normally, in WinForms, I would use InvokeRequired, but that is not available here now. When looking around I found this solution:

class SomeClass {
      private textBox_Log;
      public SomeClass(TextBox tb) {
           textBox_Log = tb;
      }

      public Log(string m) {
           Dispatcher.Invoke(() => {
               textBox_Log.Text += m + "\n";
           });
      }
}

but that complains about the Dispatcher not being available.

How can I update that TextBox from another thread (to be precise, the call originates from an event handler triggered in a FileSystemWatcher).

asked Mar 14 '20 at 13:22

Bart Friederichs

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Try to use `Application.Current.Dispatcher` or `Dispatcher` of specific window/control, like `tb.Dispatcher` – Pavel Anikhouski Mar 14 '20 at 13:31
Yes, thanks. Too bad that one doesn't show up in the Google searches :) – Bart Friederichs Mar 14 '20 at 13:37
Well, it was a first result from google search query:) – Pavel Anikhouski Mar 14 '20 at 13:39
@BartFriederichs, have you considered using `async-await` – Clint Mar 14 '20 at 13:40

Update a TextBox from another thread in WPF

0 Answers0