having an issue with IE8 - with a script that works on the other browsers perfectly

Question

So i have the following script that basically adjust the position of an element on the screen.

it works perfectly on the other browsers but cause an error on IE8

Here is the whole function call that causes the problem

function ajax_load(){
    var screenwidth = window.innerWidth
    var screenheight = window.innerHeight;
    var current_width = 250;
    var current_height = 70;
    var left = (screenwidth - current_width)/2;
    var bottom = (screenheight - current_height)/2;

    var secondajaxloaderElement = document.getElementById('ajax_loader');
    secondajaxloaderElement.style.bottom = bottom + 'px'; // Line 308 - problematic line 
    secondajaxloaderElement.style.left = left + 'px';
}

Any idea why would this fail on IE ?

The error i get from developer tool is : Invalid argument. and a line number(308) which point to secondajaxloaderElement.style.bottom = bottom + 'px';

Answer 1

Thoses are not supported in IE8:

var screenwidth = window.innerWidth
var screenheight = window.innerHeight;

http://www.w3schools.com/jsref/prop_win_innerheight.asp

See this post :

window.innerHeight ie8 alternative

This should work in IE8:

var screenwidth = document.body.clientWidth;
var screenheight = document.body.clientHeight;

Or you could also use jQuery with :

var screenwidth = $(window).width;
var screenheight = $(window).height;