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
    Introducing MooTools Templated

    One major problem with creating UI components with the MooTools JavaScript framework is that there isn't a great way of allowing customization of template and ease of node creation. As of today, there are two ways of creating: new Element Madness The first way to create UI-driven...

  • By
    Designing for Simplicity

    Before we get started, it's worth me spending a brief moment introducing myself to you. My name is Mark (or @integralist if Twitter happens to be your communication tool of choice) and I currently work for BBC News in London England as a principal engineer/tech...

Incredible Demos

  • By
    MooTools Flashlight Effect

    Another reason that I love Twitter so much is that I'm able to check out what fellow developers think is interesting. Chris Coyier posted about a flashlight effect he found built with jQuery. While I agree with Chris that it's a little corny, it...

  • By
    MooTools TextOverlap Plugin

    Developers everywhere seem to be looking for different ways to make use of JavaScript libraries. Some creations are extremely practical, others aren't. This one may be more on the "aren't" side but used correctly, my TextOverlap plugin could add another interesting design element...

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!