Set text for a TextBox control of a third party WPF application

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C#

WPF

keypress

Hi,
I intend to write an application in .Net (C#) that sets some special text for any text area of third party applications using some keyboard shortcuts.
I tried this using Send() method of SendKeys class, but problem occurs when my shortcut key is a combination of Ctrl/Alt key(s) and another key on the keyboard: When user presses the shortcut key combination, because of holding Ctrl/Alt key, the characters are sent by Send() method combine with Ctrl and result is not writing text into the text area, but doing some command.

So, I switched to a new approach and used SendMessage API using WM_SETTEXT message and everything looked good until I test my application on a WPF application.

In order to WPF structure, TextBox and all other controls on these forms have not any handle that I can use for sending messages.
Is there a solution ?