How to show Total on Footer of Gridview

Question

Hi All.,
i am using VS05.
In my application i have datagridview which is having column Quantity . I want to show Total sum of the quantity to the footer of gridview.
i have large data in my application which is bind to gridview so i have done paging for gridview. In this scinerio the sum(quantity) is come on footer for that particular page.
I want the sum(Quantity) for that particular page and Total Sum(quantity) for the gridview on footer
for eg. for page 1 - sum=10   , Page 2 - sum=30 , Page 3- sum = 10
Then  Total sum = 50
I want to do all this stuff in Inline code ie. HTML Part of page.I dont want to use code in .cs file of my page. How to do this stuff?
Thanks in advance.