Accessing the rows of a table in WebForm

Hello, I’m working on a web form that has a table Course, it has 3 fields, two read only and third one is a select type, I want to access these rows uniquely and change there values. I’ve tried something like this using jquery to access those rows but got no luck; $(’[data-child-row=1]’); it does return the row but I have no idea how could I get that particular part to get or set the value in the fields.