Question

I got a question on my codes.

I use $(this).css('opacity') to check if an element is transparent or not. When the element is transparent, it should return 0.

However, if( $(this).css('opacity') !== 0 ) executes when it returns 0. Any idea why this happens?

Thanks in advance!

My codes is here:

http://jsfiddle.net/dennisboys/f3JuH/2/

Answer 1

This is because a CSS value is always returned as a string (unlike the height and width jQuery methods, which return a number).

Try if this test works for you:

if( parseFloat($(this).css('opacity')) !== 0 )

or simply use a weak (type-coercing) inequality:

if( $(this).css('opacity') != 0 )