A IE, you never cease to amaze and surprise me!

A relatively little known, and even less appreciated, way of doing a for loop in javascript works as follows:

for (key in array) {
   var element = array[key];
   ...
}

You might recognize this as essentially the equivalent of the foreach loop in php and other languages. It's a very useful structure when dealing with associative arrays, or just to save yourself some typing. But along with obscure functionality sometimes "quirks" from time to time. Notably, as usual, in Internet Explorer.

While at work today I was looping through some form elements, in the event the page the script would run on had multiple forms. Though my test page only had a single form element in it, IE gave me multiple additional elements, such as the letter p, and the number 13...

Worse still, it did the same for the form.elements array within an inner loop. I did some investigation and found that this is a bug in IE, and has been around for a while now.

So thank you IE8, for showing us yet again that as far as you've come, you're still the bottom of the proverbial browser barrel.

Also, thank you Doug for also writing a post on this issue... albeit over 3 years ago :P I just felt I should share the fact that this is still very much an issue which IE has, even in its most recent version.

Fun Fact #372

Remember, Javascript, like most languages, short-circuits when dealing with if statements.

What does that mean?

Well for example, when running an OR evaluation with two functions, such as

if(doThis(var1) || doThat(var2){ alert("Woot!"); }

If the first function is true, the second function will not execute.

Something to keep in mind for future reference if you're wondering why your function's not running.