Calling a method within an object from a different file?

Question

Hello guys decide to refactor my javascript and try to seperate my onpage script to external js file.

please correct me if I am wrong, am still new to javascript, but this is the current setup I have:- my external file :-

exJS = function(){

  this.coolMethod = function(){
        //do cool code here
  }
}

onpage Script:-

<script type="text/javascript" src="ex_js.js"></script>
<script>
 exJs = new exJS();
 exJs.coolMethod();
</script>

So obviously I am doing something wrong, How can I call a method within an object from a different file ?

I also welcome better suggestions to carry this out

Thank you

update: It didn't work as I didn't place a comma between the functions I have defined within an object ... silly mistake !!

Why "obviously" you're doing something wrong ? You could do a little simpler but it doesn't seem so wrong. — Denys Séguret, Jan 30 '13 at 11:23
Why do you think you are doing something wrong? What does not work, what error do you get? — Bergi, Jan 30 '13 at 11:23
Note that you don't close correctly the first script element. — Denys Séguret, Jan 30 '13 at 11:25
Code is OK. First you create exJS instance and then execute coolMethod of that instance — ant_Ti, Jan 30 '13 at 11:31
ahhh it was a silly mistake, as I was declaring multiple functions within an object, I forget to seperate them by a comma, that's why I didn't work... thanks guys — HeWhoProtects, Jan 30 '13 at 12:58

score 1 · Accepted Answer · answered Jan 30 '13 at 11:25

What you do is fine (apart the badly closed first script element), but probably not needed if you don't want more than one instance of exJS.

I'd suggest this little variant :

External file :

var exJS = {
  coolMethod: function(){
        //do cool code here
  }
}

onpage Script:

<script type="text/javascript" src="ex_js.js"></script>
<script>
 exJs.coolMethod();
</script>

Note that when your code grows and you want to define a new function in another file, you may simply define this function as

exJS.doSomeOtherThing = function() {
    ...
}

score 0 · Answer 2 · edited May 23 '17 at 12:15

0

I would look at using namespaces (or at least javascripts attempt at them)

Here is an example, the accepted answer shows how to do it.

@dystroy also has an example of this in his answer.

edited May 23 '17 at 12:15

Community

answered Jan 30 '13 at 11:24

Jon Taylor

2 Answers2