How to make mathematical operations without pressing the button?

I have 2 textbox in which I enter numbers in 3 textbox automatically , you should see the sum of these numbers.
I enter the number 3, 5 in 3 textbox appears their sum. If necessary, you can change the number and the amount will change.

I don't quite understand how this can be done without pressing the button, and without pressing TextBox
April 7th 20 at 15:49
1 answer
April 7th 20 at 15:51
Catching event Control.TextChanged

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