Different approach to EDIT command in gridview

I have a gridview mainly composed of templatefields.  I want one column to be editable, but I don't like the "choose a row, click Edit, postback, enter data, click Update, postback, store changes" method.  I want to just display my (non-readonly) textboxes in this column just like any other templatefield, but have one button for the whole gridview which says "update underlying data with what the user has entered in these textboxes in these templatefields."  

For this I will need to cycle through the templatefields in my gridview, retrieving not only the values entered by the client into each textbox by row, but also the DataKey for each row so that I can make the update in the database.

Can anyone give me a down-and-dirty idea of how to accomplish this?