Two Text Boxes value in Another Textbox

Hello,
         I have on 2 text boxes. One for first name and second for last name
When ever I entered some characters in those two text boxes, I want email address as "firstname.lastname@asp.net" in third box.
Can I do this with out using Javascript. I saw few examples using Javascript but I dont want to use Javascript.
Is there any another way?


TIA

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