copy value fron gridview to other editable form

i have one grid view . in that grid view i have taken 4 Template field i.e 1.category 2.make 3.mfg.no 4.Qty and in 5th column i have taken 1 image button named as update.

Now i want that if any user click on update button a new pop-up form should get open and in that a tables should be present containing the above field parameters.u can edit it there and when u click on submit button on form 2.The grid view should get updated.

thanks in advance