Call java script function at the end of scrol

[chathura992]

Hi,

I have developed an web application which display top blogs added by the user to that website.
I am displaying data in gridview. i have given pagination to gridview.
Now i want that "if i scroll down the page, then gridview automatically expands.
Ex: Initially it contains 10 records, when i scroll down page at bottom it should show me next 10(Total 20) record, again when i scroll down it should again show me next 10(Total 30) records without refreshing the page.
This is just like facebook, when you scroll down the page it automatically shows you older posts.

i know i need ajax and java script but i have no idea how to use them should i call a java script function in on scroll method if it is so how i call that function at the end of scroll (when scroll reach to bottom of the page ) i need more explanation on that javascript function please some one help i am stuck

If anyone knows how to do this, Please reply...

Thanks,