How do you attach an event to element which should be executed only once?

Answer

 Using jQuery one() method. This attaches a handler to an event for the element. The handler is executed at most once per element. In simple terms, the attached function will be called only once.

  $(document).ready(function() {   

        $("#btnDummy").one("click", function() { 

        alert("This will be displayed only once.");     }); });