How do I get the previously focused element in JavaScript?

Question

I have an HTML form with multiple text inputs. I want to clear the element that had the focus immediately prior to when the \'Clear\' button is pressed. How do I ge

Answer 1

The simplest way is to store a reference to document.activeElement within the mousedown event on the button, although this is a mouse-centric approach and won't work for button "clicks" from keyboards and other devices.

Live demo: http://jsfiddle.net/tEP6w/

Code:

var clearButton = document.getElementById("clear");
var previousActiveElement = null;

clearButton.onmousedown = function() {
    previousActiveElement = document.activeElement;
};

clearButton.onclick = function() {
    if (previousActiveElement && previousActiveElement != this) {
        previousActiveElement.value = "";
    }
};

A better approach would be to store a reference to document.activeElement as the button is about to receive the focus. However, this is a little tricky to achieve nicely in all browsers.