RequireFieldValidation on Radiobutton Selection

Hello,
             I have one aspx page contains radio button and text box, i need to fire require field validator on the bases of radio button selection.can you help me for same


TextBox1 (Please Enter Value)

TextBox2 (Please Enter Value)
Yes(RadioButton) No (RadioButton)


Here if user select "Yes" radio button than i need to fire validation while if user select "No" than no need to fire validation.

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