Runtime create button and event

Hi,

 In a web user control I populate a table with cells at runtime.

Each cell contains a button.(this button is also created at runtime). This button has an image in background depending on it was clicked or not. I associate a click event on each button .

 

My problem is that, on a postback, I can't create the button if I don't know which button has been clicked (I need to know for the image), and I know which button has been clicked only if the button has been created (the button event raise only when the button has been created)

Any suggestion?

Thanks
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