Validate textbox if corresponding checkbox is checked

I found the following post (textbox must not be empty if checkbox is ticked) and it relates to what I want to do with my page. But how do you make this work if the checkboxes and texboxes are generated dynamically so you don't know the final number that will be present? Sometimes I have 3 checkbox and textbox pairs and other times I have 25 or more. How is this done with jquery?