if the tick box is ticked the user can select multiple values, if not ticked they can only select one value. … There are so many other javascript libraries but JQuery is most popular among them. I want to change whether a user can select only, one or multiple options in a select box based on a tick box above. You can add and remove multiple attributes with the help of JQuery by using the below code. It can be a default attribute or any custom attribute. Improve the useability of HTML