Custom textbox in expression

I have made a simple calculator in expression blend 4. I am just learning to use this. I have made custom buttons and made them into controls, and I have text boxes that 开发者_如何学JAVAI made into controls. I opened the project in visual studio and created click event for the buttons and that works, however, I can not type into the text boxes. How do I make that happen?

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Are you define new control or create only new Template?

If you define new control you must define a text-box as Content. (using template binding and set content value for text-box )
So If you define new Template and You Got mistake in it. let see your control and template!
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