c# - Calling Select() on WPF text box doesn't do anything -

I am using a WPF TextBox, and I call to calling () method Make a selection. Unfortunately, this does not seem to work until , I manually select something first. Does anyone say why such a thing happens?

Do you focus on your text box when you call the selection method?

The selection will not show until it has its focus, but the general way of focusing on the text box is by clicking on it ... which unselect the text

Select Callback Text Box (Focus) () after (or before) Select it ()

This behavior can be affected by this.