Pass form data to stream?

Question

WPF

There is a stream, everything works fine. But you need to pass data from the form to the stream

string url = Dispatcher.BeginInvoke(new ThreadStart(delegate { textBox3.Text; }));

There was such an idea, but it did not help, apparently it works in the opposite direction from the stream to the form.
Prompt how to transfer the data, in a stream from the form.

Answer 1

If when starting the thread, then like this:

var placeBetThread = new Thread(PlaceBetsWork);
placeBetThread.Start(textBox3.Text); 
private void PlaceBetsWork(object obj)
{
   var text = (string)obj;
   ...
}