How in WPF to make the dialed digits from the buttons displayed in the result row?

If you want a calculator as a standard Windows application. That is, you want to make it so that when you press the buttons with digits appear in the result string. How is this done?
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April 7th 20 at 15:31
1 answer
April 7th 20 at 15:33
See, here you will find the solution)
https://metanit.com/sharp/wpf/1.2.php

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