How can I mimic PHP $$ (double dollar sign) in jQuery

Question

First, let me just mention that this is my first attempt at a from-the-ground-up jQuery plugin.

For starters, I want my plugin to accept user defined options (+parms) via an object. For example:

<script>
    $(document).ready(function() {
        $('.myClass').augaetrk({
            myobja : {zero:'obj00 zero',one:'obj01 one',two:'obj02 two'},
            myobjb : {zero:'obj10 aaa',one:'obj11 bbb'}
        });
    }); 
</script>

Note: The names of those objects will not be predefined. They will be at the discretion of the developer using the plugin.

To cut a long story short, within the plugin I parse (for example) a link's CSS classes to identify which user parms object I should be using further into the plugin. For example.

<a class="other-class-1 this-myobja otherclass-2" href="http://mylink.com">some link</a>

I can get the class - in this case this-myobja and the name of the object I need, myobja. What I can't seem figure out is how to use that string/value as the name of the object whose parm values I want to access/utilize.

At the moment, I'm each'ing through the options and using a simple if to get to the object I want. It works but I would think I'm adding a lot of unnecessary overhead. In PHP I would use a $$ but I can't seem to find that equivalent in jQuery.

How can I take the value I'm getting from parsing the link's class= and then use the value to get corresponding (user) options?

If you're able to help please type slow and assume I know even less than you think I might know. While probably a slightly advanced programming concept, I'm by no means an advanced - or even average - jQuery developer. I'm sure you're busy but if you give an answer/example please keep in mind I'm trying to learn so a bit of explanation would be greatly appreciated. Thanks.

It would be really helpful to provide the relevant code in the form you have it working right now, because one line of code speaks a thousand words. — Jon, Dec 08 '11 at 15:21
If you are tring to do something like `var thePorpertyAsAVariable = a; obj.thePorpertyAsAVariable` then you can do `obj[thePorpertyAsAVariable]`. — prodigitalson, Dec 08 '11 at 15:25
Duplicate of [javascript equivalent of php $$ dollar dollar](http://stackoverflow.com/questions/3987057) — hippietrail, Nov 16 '12 at 05:01

score 3 · Accepted Answer · answered Dec 08 '11 at 15:27

3

If you can get the name of the relevant part of your object from the class of the a, then you can reference it like this: object["stringKey"] or object[variable]. Given your example:

// this object mimics the object passed to your plugin
var myobj = {
    myobja: {
        zero: 'obj00 zero',
        one: 'obj01 one',
        two: 'obj02 two'
    },
    myobjb: {
        zero: 'obj10 aaa',
        one: 'obj11 bbb'
    }
}

var objectName = "myobja"; // This would be the value from the A elements' class
alert(myobj[objectName].zero)

Example fiddle

answered Dec 08 '11 at 15:27

Rory McCrossan

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Hi Rory. Thanks. I suspected it was a matter of my not quite having my head wrapped around proper jQuery notation. One additional question please - How do I deal with - or not - objectName and quotes. That is, when I parse the classes to get the object name I want, do I then put that in quotes? Append quotes? – Chief Alchemist Dec 08 '11 at 17:50
Got it sorted. Thanks Rory. Those last two lines were exactly what I needed. I feel stupid, but at the same time I Googled high and low looking for an example and found nuttin'. Cheers! – Chief Alchemist Dec 08 '11 at 20:00

score 0 · Answer 2 · answered Dec 08 '11 at 15:27

0

You can use square braces to use strings as keys for objects.

var object = {};
var str = 'prop';
object[str] = 12;
console.log(object.prop); // 12

answered Dec 08 '11 at 15:27

gen_Eric

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Yes, but having them passed in as options was throwing me off. None the less, as I mentioned, my problem is probably one of notation and I think this might help too. – Chief Alchemist Dec 08 '11 at 17:55

score 0 · Answer 3 · answered Dec 08 '11 at 15:29

0

Welcome!

You're user options you'd like to receive are the objects form the above source? myobja, myobjb? So what about storing these objects in an associative array?

objects["myobja"] = myobja;
objects["myobjb"] = myobjb;

Is that somewhat helpful?

answered Dec 08 '11 at 15:29

nuala

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That's possible, I suppose. However, my bottleneck isn't how I store the parameter but how I access them as based on a value from further down the process. – Chief Alchemist Dec 08 '11 at 17:54
yeah you said start from the basics but I assumed if you know how to create an a. array you know how to pull the data back :) I see Roy edited his answer accordingly :) sorry for this! – nuala Dec 08 '11 at 20:23

How can I mimic PHP $$ (double dollar sign) in jQuery

3 Answers3