Here is some good logic for jquery guru.
I have 2 textboxes.
The hold textbox name attribute holds a value. the text box APT in its ID value holds a value.
when you type in the above text box it passes the name Attribute from APT to the text box.
What I like to happen if there is a existing value in APT that matches the same value value as hold in the textbox then update the Lst text box, if there is no value in the Hold text box the add name attribute to textbox.