for example,
var name = [1,2,3] // name === "1,2,3"
name = {"a":"b"} // name === "[object Object]"
I don't understand this situation.
what is the identity of 'name' or 'window.name' on javascript?
ADD:
I used Chrome's Dev Tools
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Ephemera
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Please have a look at [this](https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/Array/) and [this](http://www.json.org/js.html). – Adi Jul 21 '12 at 10:48
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1From **where** did you get those values? Firefox's native console? An alert? If you use Chrome's Dev Tools or Firebug it'll display the object's properties, and give a proper representation of the array. – Fabrício Matté Jul 21 '12 at 10:53
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I used Chrome's Dev Tools. but it's different from another variable. – Ephemera Jul 21 '12 at 11:05
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@Ephemera what do you mean "different" and "another variable"? – Alvin Wong Jul 21 '12 at 11:06
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If you use another variable, such as not 'name', then it is normal.( var a = [1, 2, 3] // a !== "1,2,3", a === [1,2,3]) – Ephemera Jul 21 '12 at 11:11
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I mean just focus on 'name' or 'window.name' – Ephemera Jul 21 '12 at 11:16
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In browser's JavaScript, all "global" variable are under the `window` object. – Alvin Wong Jul 21 '12 at 12:20
1 Answers
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When you declare
name = {"a":"b"}
you are creating an object and the string representation of an object is [object Object], that is, when you try to convert an object to a string (which is probably the case here) you get that result.
Note that name === "[object Object]" is not true.
alert( name === "[object Object]" ); // alerts "false"
alert( name.toString() === "[object Object]" ); // alerts "true"
The same holds true for the array. 1,2,3 is just a string representation of array [1,2,3].
As for window.name, it has the name of the current window so changing it to a non-string might lead to unexpected behavior: https://developer.mozilla.org/en/DOM/window.name
JJJ
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String representation.. You could also add that whatever way OP is displaying these "values" is forcing them to be cast to strings. – Fabrício Matté Jul 21 '12 at 10:57
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You may like to state that `typeof name` is to be used for type checking rather than using `name.toString()` to avoid confusion – Alvin Wong Jul 21 '12 at 11:00
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@AlvinWong I thought about it, but it might be confusing in this case since `typeof [1,2,3] === 'object'`. – JJJ Jul 21 '12 at 11:02
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Firebug is fine. You are right. but try on Chrome's Dev Tool. It's a little strange. – Ephemera Jul 21 '12 at 11:03
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If you use another variable, such as not 'name', then it is normal.( var a = [1, 2, 3] // a !== "1,2,3", a === [1,2,3]) – Ephemera Jul 21 '12 at 11:12
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2@Ephemera because `window.name` is supposed to be a string. Some engine may automatically convert it to a string. – Alvin Wong Jul 21 '12 at 12:19
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@AlvinWong I think you are right. Just Chrome's policy(?) is reason. Thanks every body. – Ephemera Jul 21 '12 at 12:42