Why did I get "Undefined" message?

Question

I have defined a object in a js file:

myobj.js

MyObj={
  test: {
     startTest: function(){
         var x = SOME_PROCESS_A;
         var y = SOME_PROCESS_B;
         return {x: x, y: y};
     }
  }
}

In another js file I call this object function:

other.js

var mytest = MyObj.test.startTest
var a = mytest.x;
var b = mytest.y;

my index.html:

<body>
 <script src="myobj.js"></script>
 <script src="other.js"></script>
</body>

I got the error from firebug in other.js, "mytest" is undfined in the line "var a = mytest.x;" Why??

Thank you,all. I got another "undefined" problem in the similar code, please check here

you should use it like a function: var mytest = MyObj.test.startTest() — Vlad Khomich, Apr 18 '11 at 07:43

score 3 · Answer 1 · answered Apr 18 '11 at 07:39

3

You have forgot to call the function:

var mytest = MyObj.test.startTest()

answered Apr 18 '11 at 07:39

Eldar Djafarov

23,327
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Headshota · Answer 2 · 2011-04-18T07:57:07.730

1

becouse mytest is a function object, and there are no properties defined in it.

you can either call it like

MyObj.test.startTest();

or rewrite your object something like:

MyObj={
  test: {
     startTest: function(){
         this.x = SOME_PROCESS_A;
         this.y = SOME_PROCESS_B;
         return {x: this.x, y: this.y};
     }
  }
}

edited Apr 18 '11 at 07:57

answered Apr 18 '11 at 07:40

Headshota

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*"becouse mytest is a function object, it doesn't have properties"* Functions do have properties, and you can even add your own. Specifically in this case, though, this particular function doesn't have the `x` and `y` properties. – T.J. Crowder Apr 18 '11 at 07:48
yes I meant this particular function. I will correct my answer, thanks ;) – Headshota Apr 18 '11 at 07:56
Thank you, but I got another undefined error, here : http://stackoverflow.com/questions/5700054/variable-is-not-defined-error-why – Mellon Apr 18 '11 at 08:03

score 1 · Accepted Answer · answered Apr 18 '11 at 07:41

1

I think you meant to do

var mytest = MyObj.test.startTest(); //calls the function and returns the value to mytest

and not

var mytest = MyObj.test.startTest;//assigns the function to mytest

answered Apr 18 '11 at 07:41

JohnP

49,507
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Thank you. but I got another undefined error, here http://stackoverflow.com/questions/5700054/variable-is-not-defined-error-why – Mellon Apr 18 '11 at 08:02
@Mellon, you shouldn't post a new question. It will likely be closed as duplicate. Update this question – JohnP Apr 18 '11 at 08:03

Why did I get "Undefined" message?

3 Answers3

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