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[Newb] How to reference object by string+var

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  [Newb] How to reference object by string+var skoskie <smkoskie@gmail.com> - 2012-06-26 10:21 -0700
    Re: [Newb] How to reference object by string+var Mike Winter <usenet@michael-winter.me.invalid> - 2012-06-26 20:06 +0100
      Re: [Newb] How to reference object by string+var skoskie <smkoskie@gmail.com> - 2012-06-26 13:40 -0700

#14671 — [Newb] How to reference object by string+var

I'm trying to reference a google maps object by concatenating a string and a var but see no way of doing so. Super newb to JS. Any help would be greatly appreciated. 

URL: example.com?locationID=254

Simplified example of code:
========================
var location = getUrlVar('locationID'); <-- Works!
markerInfo.open( 'marker'+location );
========================

So you can see that "marker254" is an object I need to pass reference to. I've tried to use eval(), but it didn't work for me and from what I've read it's not the most secure approach anyway. 

Thanks in advance for any assistance. 

S. 

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#14681

On 26/06/2012 18:21, skoskie wrote:

> I'm trying to reference a google maps object by concatenating a string and a var but see no way of doing so. Super newb to JS. Any help would be greatly appreciated.
>
> URL: example.com?locationID=254
>
> Simplified example of code:
> ========================
> var location = getUrlVar('locationID'); <-- Works!
> markerInfo.open( 'marker'+location );
> ========================
>
> So you can see that "marker254" is an object I need to pass reference to. I've tried to use eval(), but it didn't work for me and from what I've read it's not the most secure approach anyway.

Hi,

In what scope is the object, marker254? If it can be accessed as a 
property of some object ('container' below) then you can construct a 
property name using bracket notation:

   container['marker' + location]

If it's a global variable then it can be accessed as a property of the 
window object or an equivalent reference. If it's a local variable this 
is more tricky and you'd be better off assigning it as a property of 
some plain object that you'd then use like a map. Without knowing more 
about your existing code, I can't provide anything more than a contrived 
example to demonstrate this:

   var markers = {};
   // ...
   markers.marker254 = new Marker();  // or simply markers[254] ?
   // ...
   markerInfo.open(markers['marker' + location]);

Hope that helps,
Mike

-- 
Michael Winter
Replace ".invalid" with ".uk" to reply by e-mail.

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#14687

Bracket! That worked. It was exactly what I needed. Thanks so much. 

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