JavaScript Arrays: The Difference Between [] and { }
Using Moo 1.2 has taught me a lot about JavaScript. Of course, that means I've made a lot of mistakes but that seems to be the best way for me to learn. While browsing the Moo source, I'd always wondered the difference between arrays using brackets ([]) and braces ({}). Here's what I learned.
Use brackets for an array of simple values.
//examples var answers = ['yes','no','maybe']; var names = ['David','Kristina','Charlie','Angela'];
Use braces for key => value arrays and objects/properties.
//example - random array
var programmer = { 'name':'David Walsh', 'url':'https://davidwalsh.name', 'girl':'Kristina'}
//example - used for an object's properties
var Element.implement({
getText: function(){
return this.get('text');
}
});
This is similar to PHP's array system.
$arr = array('name'=>'David','position'=>'Programmer');
Have anything to add? Please share!
This is interesting. So if you use []’s in a key=>value array it just won’t work or it’s simply improper usage?
I must admit, I’ve wondered this myself with the MOO as they seem to have pretty creative looking code conventions (that really make a lot of sense).
@Tim: That’s what I get from it. Please let me know if I’m wrong.
I feel like you’re missing one of the finer points in this bracket/brace post; braces define Objects – not Arrays!
The following are essentially the same:
… as are:
var myObject = {}; var myObject = new Object();Javascript is by no means perfect – so you’ll have to know the pitfalls, like erroneously mixing keys and indexes in an Array (like you can do in PHP – bad).
As javascript doesn’t have associative arrays Objects are the closest thing.
Ahh!! I am so enlightened by that! Thank you! That makes so much sense now! Too many exclamations!! I need to stop but can’t!
On a serious note, that does clarify a few questions I had.
Thanks David
U solved my problem. I am first time using Javascript in my website and i was getting one problem with one line.
mycarousel_itemList[counter]= [{url: "ID,'thumbnail', true); ?>",link: "",title: ""}] ;and u solved it … thanks again…regards
Thanks Rasmus. This is what Exactly i was looking for.
I’m not new to JavaScript but trying to move forward, what seems to be a mistery to me is the use of punctuation ( ‘.,’:([{‘ )???. and the rules they surely must adhere too. Not one tutorial (and I have explored a lot) explains what these things actually mean and where they are to be used. It almost seems arbitrary, like learning the bizarre ‘illogical’ rules of a spoken language. Can yo help?
Regards,
Richard.