KeyPress method does not work due to no reference

There are several KeyPress method in my code. All are working except the one due to no reference. I have checked the project for naming mistake. But there is no any mistake. How can I make reference for this method.

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btnback_KeyPress is not working.

Looks like you just don't have the event hooked up. Go into the designer, select the btnback button, then in the Events tab of the Properties window, find the KeyPress event and subscribe the btnback_KeyPress method to it as a handler.

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