ModalPopup, validation, clear controls

I have a ModalPopup that contains a few controls, and there's a submit button in it to submit the data.  There are also validation controls for all the fields in the popup.  I have some problems though:
The data doesn't clear after I click the button.  The page will perform a postback, and when the page loads again and I click to open the Modal, all the information is still in thereThe data doesn't clear after I click the CLOSE button.  If I open it again, the data is still there.When I initially go to the page and open the modal, the fields are empty.  However, all the validation controls are visible, saying that I need to enter data in the fields.  I don't want the validation controls to show until after I've hit the Submit button. Please help
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