After the WPF textbox gets the focus, select all text in the text box.

Textbox. gotfocus event processing textbox. selectall () is not acceptable, so the processing will happen:
1) textbox1 currently has no focus and the content is sometext.
2) Click textbox1. If the clicked point is within sometext, all options after sometext is selected are canceled. If the clicked point is outside sometext, nothing will happen, no selected content.

 

The solution is as follows:

 

Public partial class mainwindow: window {public mainwindow () {initializecomponent (); like_textbox.previewmousedown + = new mousebuttoneventhandler (like_textbox_previewmousedown); // note, registration of this event must be performed before like_textbox obtains the Focus + = new routedeventhandler (handler); handler + = new routedeventhandler (handler);} void like_textbox_lostfocus (Object sender, routedeventargs E) {callback + = new mousebuttoneventhandler (like_textbox_previewmousedown);} void like_textbox_previewmousedown (Object sender, mousebuttoneventargs e) {like_textbox.focus (); E. handled = true;} void like_textbox_gotfocus (Object sender, routedeventargs e) {like_textbox.selectall (); callback-= new mousebuttoneventhandler (like_textbox_previewmousedown );}}

 

After the WPF textbox gets the focus, select all text in the text box.