Working around IE8's broken Object.defineProperty implementation

Question

Consider the following code, using ECMAScript5\'s Object.defineProperty feature:

var sayHi = function(){ alert(\'hi\'); };
var defineProperty =          


        

Answer 1

I had the same kind issue (i.e. the Object.defineProperty in IE 8 being DOM only and not a full implementation as the other browsers), but it was for a polyfill..

Anyhoo, I ended using a 'feature' check to see if I was using IE, its not perfect, but it works on all the tests I could do:

if (Object.defineProperty && !document.all && document.addEventListener) {
    Object.defineProperty(Array.prototype,'sayHi',{value:sayHi});
} else {
    Array.prototype.sayHi = sayHi;
}

as IE <= 8 has no document.addEventListener, and document.all is a proprietary Microsoft extension to the W3C standard. These two checks are equivalent to checking if IE is version 8 or below.