how to create sqldatasource for dropdownlist into gridview

Question

Hi Guys

Please help me

I have to Dropdownlist put into FooterTemplate in Gridview how to make sqldatasource is working as dropdownlist as control ID in webform very easy but i did not know into internal girdview.

pls see the photo below support the problem :

see to the last 2 dropdownlist . DropDownlist5 is Region and DropDownlist is City in order to filter cities according to regions .