Create and Retrieve Nested Objects with jQuery

By  on  

The ability to create and retrieve nested objects by objectified string path is incredibly useful.  Not only do you not need to do the manual string of object/property checks to avoid "{x} is not defined" errors, but if you create your method properly, you can also set an empty object in its given place (or namespace, some would call it.    Here's how you can add this functionality to the jQuery object.

The jQuery JavaScript

Since jQuery's philosophy is to use the same method for getting and setting, we'll be doing this same for creating and retrieving objects;  in this case, we'll use the obj method:

(function() {

	// Utility method to get and set objects that may or may not exist
	var objectifier = function(splits, create, context) {
		var result = context || window;
		for(var i = 0, s; result && (s = splits[i]); i++) {
			result = (s in result ? result[s] : (create ? result[s] = {} : undefined));
		}
		return result;
	};

	// Gets or sets an object
	jQuery.obj = function(name, value, create, context) {
		// Setter
		if(value != undefined) {
			var splits = name.split("."), s = splits.pop(), result = objectifier(splits, true, context);
			return result && s ? (result[s] = value) : undefined;
		}
		// Getter
		else {
			return objectifier(name.split("."), create, context);
		}
	};

})();

As with the MooTools alternative, the objectifier function is enough to handle both getting and setting, as well as doing both within a given context (existing object).  Here are a few examples of how you can use the new jQuery.obj method:

// Check for existence
var moduleNameExists = jQuery.obj("mynamespace.widget.moduleName"); // undefined

// Create the obj
jQuery.obj("mynamespace.widget.moduleName", { prop: 1 }); // mynamespace.widget.moduleName.prop returns 1

// Create an object on existing object
jQuery.obj("subnamespace.subModuleName", { someProp: 8 }, true, mynamespace.widget);
	// mynamespace.widget.subnamespace.subModuleName = { someProp: 8 }

As I work more with jQuery, both with its provided methods and other third party tools, accessing arbitrary objects by string and sometimes context allows me to avoid the dance of manual object and property existence checks.  Of course the essence of this script is really the objectifier method, which can be added to any framework or toolkit, but with a framework as popular as jQuery, why not just put it out there for everyone?

Recent Features

  • By
    Write Better JavaScript with Promises

    You've probably heard the talk around the water cooler about how promises are the future. All of the cool kids are using them, but you don't see what makes them so special. Can't you just use a callback? What's the big deal? In this article, we'll...

  • By
    I’m an Impostor

    This is the hardest thing I've ever had to write, much less admit to myself.  I've written resignation letters from jobs I've loved, I've ended relationships, I've failed at a host of tasks, and let myself down in my life.  All of those feelings were very...

Incredible Demos

  • By
    The Simple Intro to SVG Animation

    This article serves as a first step toward mastering SVG element animation. Included within are links to key resources for diving deeper, so bookmark this page and refer back to it throughout your journey toward SVG mastery. An SVG element is a special type of DOM element...

  • By
    Create a Download Package Using MooTools Moousture

    Zohaib Sibt-e-Hassan recently released a great mouse gestures library for MooTools called Moousture. Moousture allows you to trigger functionality by moving your mouse in specified custom patterns. Too illustrate Moousture's value, I've created an image download builder using Mooustures and PHP. The XHTML We provide...

Discussion

  1. Any chance that there is a demo or functional example of this available? I’m trying to use this to create nested dropdown boxes based on jQuery UI’s nested menu, and I’m having some difficulty understanding how to apply the objectifier function.

Wrap your code in <pre class="{language}"></pre> tags, link to a GitHub gist, JSFiddle fiddle, or CodePen pen to embed!