how to make textbox text will not disappear on button click event?

I have TextBox and button1 on my asp.net webform.

I want when I click button1 then the text on the TextBox will remain the same as it is. It will not disappear, on butto开发者_如何学Gon click event.

I want vb.net code to do this

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You need to make sure that you have ViewState enabled - it is enabled by default but it is possible that you have disabled it (either for the TextBox, or possibly for the entire page).