i tried overflow property and it worked ,:)
but don't you think that adding 20 columns to gridview isn't a good practice ?
am i doing right bcz it looks little ugly on page, any other way to get around ?
You should include any fields that aren't required for that view. I would only include the most important fields (maybe two or three), then make one of the fields as a hyperlink field so that when the user clicks on it you can either show a detailsview control on another page with all 20 fields.