insert gridveiw rows in a list

See more:

ASP.NET

hello sir. i have a gridview with 15 columns. i inserting rows to the gridview from 15 textboxes using datatable. when ever i am inserting one row, it is displaying below. when ever insert second row first row is moving up and second row is inserting below.
my requirement is bydefault gridview has to display 5 empty rows. when ever i isnert one row, it is displayed on first row, when ever i isnert second row, it has to display on the second row, till 5 rows like this. when ever i insert 6th row first row is moving up and 6 th row is displayed on the list,i mean gridview has to display 5 rows at a time. i put scroll bar to gridview.
if any body know how to do this. plz help me.
thanking you sir.