I do have a radgrid and inside one column i am using another radgrid which has checkbox, userid, ssn.
on submit button, is it possible to loop through radgrid on client side and get all the ssn's? I would like to concatenate the ssn's separated by comma.
You could take a look at the accessing cells and rows documentation article. Although it seems you might not be able to just cycle through every row - there are methods to extract values from cells if you follow the links to the client-side functions.