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JavaScript Object-Oriented JavaScript (2015) Introduction to Methods Returning Values

Posted by Rachel Heneault
Rachel Heneault
12,401 Points

Method on the button

In the dom manipulation class they about event listeners. When you put the method on the button its like add event listener. I just wonder when do you choose to use the event listener method? This seems way more simplistic, and I like it. Is it just a personal preference?

var button = document.getElementById("button");

button.onclick = function() { var result = 1; printNumber(result); };

1 Answer

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

Two differences come to mind:

  • the onclick property supports only one handler, addEventListener can be used to create multiple handlers
  • onclick attaches only a direct handler, with addEventListener the handler can be direct or delegated

So if you need only one direct handler, the onclick property is a handy shortcut.