Check element CSS display with JavaScript

As sdleihssirhc says below, if the element's display is being inherited or being specified by a CSS rule, you'll need to get its computed style:

return window.getComputedStyle(element, null).display;

Elements have a style property that will tell you what you want, if the style was declared inline or with JavaScript:

console.log(document.getElementById('someIDThatExists').style.display);

will give you a string value.

If the style was declared inline or with JavaScript, you can just get at the style object:

return element.style.display === 'block';

Otherwise, you'll have to get the computed style, and there are browser inconsistencies. IE uses a simple currentStyle object, but everyone else uses a method:

return element.currentStyle ? element.currentStyle.display :
                              getComputedStyle(element, null).display;

The null was required in Firefox version 3 and below.

For jQuery, do you mean like this?

$('#object').css('display');

You can check it like this:

if($('#object').css('display') === 'block')
{
    //do something
}
else
{
    //something else
}