c# - WPF Application stealing focus -

what want do:

i want wpf app type in keystrokes onto other application has text fields, example, notepad.

what problem is:

if press button simulates keystroke ('a', example), app steals focus , 'notepad' not focused/active anymore, button not know send keystroke,

what im requesting: how wpf app not steal focus of other app can type in keystroke when press app's buttons, here's code:

 private void button_click(object sender, routedeventargs e)     {          inputsimulator.simulatetextentry("1");      } 

'inputsimulator' comes library got online, makes simulating keystrokes easy.

**update, clarification, want surface pro keyboard, keyboard want do, if press on it's keyboard, app active stays focused , sp3 keyboard able enter keystroke, how do app?

you'll need p/invoke user32.dll, use findwindow handle application trying write to, use setforegroundwindow. can send keystrokes window.

see article on msdn quick sample: https://msdn.microsoft.com/en-us/library/ms171548.aspx

you can find tons of examples searching google p/invoke , windows api.