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After an AJAX request, sometimes my application may return an empty object, like:
var a = {};
How can I check whether that's the case?
ECMA 5+:
// because Object.keys(new Date()).length === 0;
// we have to do some additional check
obj // 👈 null and undefined check
&& Object.keys(obj).length === 0
&& Object.getPrototypeOf(obj) === Object.prototype
Note, though, that this creates an unnecessary array (the return value of keys).
Pre-ECMA 5:
function isEmpty(obj) {
for(var prop in obj) {
if(Object.prototype.hasOwnProperty.call(obj, prop)) {
return false;
}
}
return JSON.stringify(obj) === JSON.stringify({});
}
jQuery:
jQuery.isEmptyObject({}); // true
lodash:
_.isEmpty({}); // true
Underscore:
_.isEmpty({}); // true
Hoek
Hoek.deepEqual({}, {}); // true
ExtJS
Ext.Object.isEmpty({}); // true
AngularJS (version 1)
angular.equals({}, {}); // true
Ramda
R.isEmpty({}); // true
If ECMAScript 5 support is available, you can use Object.keys():
function isEmpty(obj) {
return Object.keys(obj).length === 0;
}
For ES3 and older, there's no easy way to do this. You'll have to loop over the properties explicitly:
function isEmpty(obj) {
for(var prop in obj) {
if(obj.hasOwnProperty(prop))
return false;
}
return true;
}
For those of you who have the same problem but use jQuery, you can use jQuery.isEmptyObject.
Performance
Today 2020.01.17, I performed tests on macOS High Sierra 10.13.6 on Chrome v79.0, Safari v13.0.4, and Firefox v72.0; for the chosen solutions.
Conclusions
Solutions based on for-in (A, J, L, M) are fastest
Solutions based on JSON.stringify (B, K) are slow
Surprisingly, the solution based on Object (N) is also slow
NOTE: This table does not match the photo below.
Details
There are 15 solutions presented in the snippet below.
If you want to run a performance test on your machine, click HERE.
This link was updated 2021.07.08, but tests originally were performed here - and results in the table above came from there (but now it looks like that service no longer works).
var log = (s, f) => console.log(`${s} --> {}:${f({})} {k:2}:${f({ k: 2 })}`);
function A(obj) {
for (var i in obj) return false;
return true;
}
function B(obj) {
return JSON.stringify(obj) === "{}";
}
function C(obj) {
return Object.keys(obj).length === 0;
}
function D(obj) {
return Object.entries(obj).length === 0;
}
function E(obj) {
return Object.getOwnPropertyNames(obj).length === 0;
}
function F(obj) {
return Object.keys(obj).length === 0 && obj.constructor === Object;
}
function G(obj) {
return typeof obj === "undefined" || !Boolean(Object.keys(obj)[0]);
}
function H(obj) {
return Object.entries(obj).length === 0 && obj.constructor === Object;
}
function I(obj) {
return Object.values(obj).every((val) => typeof val === "undefined");
}
function J(obj) {
for (const key in obj) {
if (hasOwnProperty.call(obj, key)) {
return false;
}
}
return true;
}
function K(obj) {
for (var prop in obj) {
if (obj.hasOwnProperty(prop)) {
return false;
}
}
return JSON.stringify(obj) === JSON.stringify({});
}
function L(obj) {
for (var prop in obj) {
if (obj.hasOwnProperty(prop)) return false;
}
return true;
}
function M(obj) {
for (var k in obj) {
if (obj.hasOwnProperty(k)) {
return false;
}
}
return true;
}
function N(obj) {
return (
Object.getOwnPropertyNames(obj).length === 0 &&
Object.getOwnPropertySymbols(obj).length === 0 &&
Object.getPrototypeOf(obj) === Object.prototype
);
}
function O(obj) {
return !(Object.getOwnPropertyNames !== undefined
? Object.getOwnPropertyNames(obj).length !== 0
: (function () {
for (var key in obj) break;
return key !== null && key !== undefined;
})());
}
log("A", A);
log("B", B);
log("C", C);
log("D", D);
log("E", E);
log("F", F);
log("G", G);
log("H", H);
log("I", I);
log("J", J);
log("K", K);
log("L", L);
log("M", M);
log("N", N);
log("O", O);
You can use Underscore.js.
_.isEmpty({}); // true
if(Object.getOwnPropertyNames(obj).length === 0){
//is empty
}
see http://bencollier.net/2011/04/javascript-is-an-object-empty/
How about using JSON.stringify? It is almost available in all modern browsers.
function isEmptyObject(obj){
return JSON.stringify(obj) === '{}';
}
There is a simple way if you are on a newer browser.
Object.keys(obj).length === 0
Old question, but just had the issue. Including JQuery is not really a good idea if your only purpose is to check if the object is not empty. Instead, just deep into JQuery's code, and you will get the answer:
function isEmptyObject(obj) {
var name;
for (name in obj) {
if (obj.hasOwnProperty(name)) {
return false;
}
}
return true;
}
Using Object.keys(obj).length (as suggested above for ECMA 5+) is 10 times slower for empty objects! keep with the old school (for...in) option.
Tested under Node, Chrome, Firefox and IE 9, it becomes evident that for most use cases:
(for...in...) is the fastest option to use!
Object.keys(obj).length is 10 times slower for empty objects
JSON.stringify(obj).length is always the slowest (not suprising)
Object.getOwnPropertyNames(obj).length takes longer than Object.keys(obj).length can be much longer on some systems.
Bottom line performance wise, use:
function isEmpty(obj) {
for (var x in obj) { return false; }
return true;
}
or
function isEmpty(obj) {
for (var x in obj) { if (obj.hasOwnProperty(x)) return false; }
return true;
}
See detailed testing results and test code at Is object empty?
My take:
function isEmpty(obj) {
return Object.keys(obj).length === 0;
}
var a = {
a: 1,
b: 2
}
var b = {}
console.log(isEmpty(a)); // false
console.log(isEmpty(b)); // true
Just, I don't think all browsers implement Object.keys() currently.
I am using this.
function isObjectEmpty(object) {
var isEmpty = true;
for (keys in object) {
isEmpty = false;
break; // exiting since we found that the object is not empty
}
return isEmpty;
}
Eg:
var myObject = {}; // Object is empty
var isEmpty = isObjectEmpty(myObject); // will return true;
// populating the object
myObject = {"name":"John Smith","Address":"Kochi, Kerala"};
// check if the object is empty
isEmpty = isObjectEmpty(myObject); // will return false;
from here
Update
OR
you can use the jQuery implementation of isEmptyObject
function isEmptyObject(obj) {
var name;
for (name in obj) {
return false;
}
return true;
}
Just a workaround. Can your server generate some special property in case of no data?
For example:
var a = {empty:true};
Then you can easily check it in your AJAX callback code.
Another way to check it:
if (a.toSource() === "({})") // then 'a' is empty
EDIT:
If you use any JSON library (f.e. JSON.js) then you may try JSON.encode() function and test the result against empty value string.
1. Using Object.keys
Object.keys will return an Array, which contains the property names of the object. If the length of the array is 0, then we know that the object is empty.
function isEmpty(obj) {
return Object.keys(obj).length === 0 && obj.constructor === Object;
}
We can also check this using Object.values and Object.entries.
This is typically the easiest way to determine if an object is empty.
2. Looping over object properties with for…in
The for…in statement will loop through the enumerable property of object.
function isEmpty(obj) {
for(var prop in obj) {
if(obj.hasOwnProperty(prop))
return false;
}
return true;
}
In the above code, we will loop through object properties and if an object has at least one property, then it will enter the loop and return false. If the object doesn’t have any properties then it will return true.
#3. Using JSON.stringify
If we stringify the object and the result is simply an opening and closing bracket, we know the object is empty.
function isEmptyObject(obj){
return JSON.stringify(obj) === '{}';
}
4. Using jQuery
jQuery.isEmptyObject(obj);
5. Using Underscore and Lodash
_.isEmpty(obj);
Resource
function isEmpty(obj) {
for(var i in obj) { return false; }
return true;
}
The following example show how to test if a JavaScript object is empty, if by empty we means has no own properties to it.
The script works on ES6.
const isEmpty = (obj) => {
if (obj === null ||
obj === undefined ||
Array.isArray(obj) ||
typeof obj !== 'object'
) {
return true;
}
return Object.getOwnPropertyNames(obj).length === 0;
};
console.clear();
console.log('-----');
console.log(isEmpty('')); // true
console.log(isEmpty(33)); // true
console.log(isEmpty([])); // true
console.log(isEmpty({})); // true
console.log(isEmpty({ length: 0, custom_property: [] })); // false
console.log('-----');
console.log(isEmpty('Hello')); // true
console.log(isEmpty([1, 2, 3])); // true
console.log(isEmpty({ test: 1 })); // false
console.log(isEmpty({ length: 3, custom_property: [1, 2, 3] })); // false
console.log('-----');
console.log(isEmpty(new Date())); // true
console.log(isEmpty(Infinity)); // true
console.log(isEmpty(null)); // true
console.log(isEmpty(undefined)); // true
The correct answer is:
function isEmptyObject(obj) {
return (
Object.getPrototypeOf(obj) === Object.prototype &&
Object.getOwnPropertyNames(obj).length === 0 &&
Object.getOwnPropertySymbols(obj).length === 0
);
}
This checks that:
The object's prototype is exactly Object.prototype.
The object has no own properties (regardless of enumerability).
The object has no own property symbols.
In other words, the object is indistinguishable from one created with {}.
jQuery have special function isEmptyObject() for this case:
jQuery.isEmptyObject({}) // true
jQuery.isEmptyObject({ foo: "bar" }) // false
Read more on http://api.jquery.com/jQuery.isEmptyObject/
Caveat! Beware of JSON's limitiations.
javascript:
obj={ f:function(){} };
alert( "Beware!! obj is NOT empty!\n\nobj = { f:function(){} }" +
"\n\nJSON.stringify( obj )\n\nreturns\n\n" +
JSON.stringify( obj ) );
displays
Beware!! obj is NOT empty!
obj = { f:function(){} }
JSON.stringify( obj )
returns
{}
To really accept ONLY {}, the best way to do it in Javascript using Lodash is:
_.isEmpty(value) && _.isPlainObject(value)
In addition to Thevs answer:
var o = {};
alert($.toJSON(o)=='{}'); // true
var o = {a:1};
alert($.toJSON(o)=='{}'); // false
it's jquery + jquery.json
Sugar.JS provides extended objects for this purpose. The code is clean and simple:
Make an extended object:
a = Object.extended({})
Check it's size:
a.size()
Pure Vanilla Javascript, and full backward compatibility
function isObjectDefined (Obj) {
if (Obj === null || typeof Obj !== 'object' ||
Object.prototype.toString.call(Obj) === '[object Array]') {
return false
} else {
for (var prop in Obj) {
if (Obj.hasOwnProperty(prop)) {
return true
}
}
return JSON.stringify(Obj) !== JSON.stringify({})
}
}
console.log(isObjectDefined()) // false
console.log(isObjectDefined('')) // false
console.log(isObjectDefined(1)) // false
console.log(isObjectDefined('string')) // false
console.log(isObjectDefined(NaN)) // false
console.log(isObjectDefined(null)) // false
console.log(isObjectDefined({})) // false
console.log(isObjectDefined([])) // false
console.log(isObjectDefined({a: ''})) // true
IsEmpty Object, unexpectedly lost its meaning i.e.: it's programming semantics, when our famous guru from Yahoo introduced the customized non-enumerable Object properties to ECMA and they got accepted.
[ If you don't like history - feel free to skip right to the working code ]
I'm seeing lots of good answers \ solutions to this question \ problem.
However, grabbing the most recent extensions to ECMA Script is not the honest way to go. We used to hold back the Web back in the day to keep Netscape 4.x, and Netscape based pages work and projects alive, which (by the way) were extremely primitive backwards and idiosyncratic, refusing to use new W3C standards and propositions [ which were quite revolutionary for that time and coder friendly ] while now being brutal against our own legacy.
Killing Internet Explorer 11 is plain wrong! Yes, some old warriors that infiltrated Microsoft remaining dormant since the "Cold War" era, agreed to it - for all the wrong reasons. - But that doesn't make it right!
Making use, of a newly introduced method\property in your answers and handing it over as a discovery ("that was always there but we didn't notice it"), rather than a new invention (for what it really is), is somewhat 'green' and harmful. I used to make such mistakes some 20 years ago when I still couldn't tell what's already in there and treated everything I could find a reference for, as a common working solution...
Backward compatibility is important !
We just don't know it yet. That's the reason I got the need to share my 'centuries old' generic solution which remains backward and forward compatible to the unforeseen future.
There were lots of attacks on the in operator but I think the guys doing that have finally come to senses and really started to understand and appreciate a true Dynamic Type Language such as JavaScript and its beautiful nature.
My methods aim to be simple and nuclear and for reasons mentioned above, I don't call it "empty" because the meaning of that word is no longer accurate. Is Enumerable, seems to be the word with the exact meaning.
function isEnum( x ) { for( var p in x )return!0; return!1 };
Some use cases:
isEnum({1:0})
true
isEnum({})
false
isEnum(null)
false
Thanks for reading!
Best one-liner solution I could find (updated):
isEmpty = obj => !Object.values(obj).filter(e => typeof e !== 'undefined').length;
console.log(isEmpty({})) // true
console.log(isEmpty({a: undefined, b: undefined})) // true
console.log(isEmpty({a: undefined, b: void 1024, c: void 0})) // true
console.log(isEmpty({a: [undefined, undefined]})) // false
console.log(isEmpty({a: 1})) // false
console.log(isEmpty({a: ''})) // false
console.log(isEmpty({a: null, b: undefined})) // false
Another alternative is to use is.js (14kB) as opposed to jquery (32kB), lodash (50kB), or underscore (16.4kB). is.js proved to be the fastest library among aforementioned libraries that could be used to determine whether an object is empty.
http://jsperf.com/check-empty-object-using-libraries
Obviously all these libraries are not exactly the same so if you need to easily manipulate the DOM then jquery might still be a good choice or if you need more than just type checking then lodash or underscore might be good. As for is.js, here is the syntax:
var a = {};
is.empty(a); // true
is.empty({"hello": "world"}) // false
Like underscore's and lodash's _.isObject(), this is not exclusively for objects but also applies to arrays and strings.
Under the hood this library is using Object.getOwnPropertyNames which is similar to Object.keys but Object.getOwnPropertyNames is a more thorough since it will return enumerable and non-enumerable properties as described here.
is.empty = function(value) {
if(is.object(value)){
var num = Object.getOwnPropertyNames(value).length;
if(num === 0 || (num === 1 && is.array(value)) || (num === 2 && is.arguments(value))){
return true;
}
return false;
} else {
return value === '';
}
};
If you don't want to bring in a library (which is understandable) and you know that you are only checking objects (not arrays or strings) then the following function should suit your needs.
function isEmptyObject( obj ) {
return Object.getOwnPropertyNames(obj).length === 0;
}
This is only a bit faster than is.js though just because you aren't checking whether it is an object.
I know this doesn't answer 100% your question, but I have faced similar issues before and here's how I use to solve them:
I have an API that may return an empty object. Because I know what fields to expect from the API, I only check if any of the required fields are present or not.
For example:
API returns {} or {agentID: '1234' (required), address: '1234 lane' (opt),...}.
In my calling function, I'll only check
if(response.data && response.data.agentID) {
do something with my agentID
} else {
is empty response
}
This way I don't need to use those expensive methods to check if an object is empty. The object will be empty for my calling function if it doesn't have the agentID field.
We can check with vanilla js with handling null or undefined check also as follows,
function isEmptyObject(obj) {
return !!obj && Object.keys(obj).length === 0 && obj.constructor === Object;
}
//tests
isEmptyObject(new Boolean()); // false
isEmptyObject(new Array()); // false
isEmptyObject(new RegExp()); // false
isEmptyObject(new String()); // false
isEmptyObject(new Number()); // false
isEmptyObject(new Function()); // false
isEmptyObject(new Date()); // false
isEmptyObject(null); // false
isEmptyObject(undefined); // false
isEmptyObject({}); // true
I liked this one I came up with, with the help of some other answers here. Thought I'd share it.
Object.defineProperty(Object.prototype, 'isEmpty', {
get() {
for(var p in this) {
if (this.hasOwnProperty(p)) {return false}
}
return true;
}
});
let users = {};
let colors = {primary: 'red'};
let sizes = {sm: 100, md: 200, lg: 300};
console.log(
'\nusers =', users,
'\nusers.isEmpty ==> ' + users.isEmpty,
'\n\n-------------\n',
'\ncolors =', colors,
'\ncolors.isEmpty ==> ' + colors.isEmpty,
'\n\n-------------\n',
'\nsizes =', sizes,
'\nsizes.isEmpty ==> ' + sizes.isEmpty,
'\n',
''
);
It's weird that I haven't encountered a solution that compares the object's values as opposed to the existence of any entry (maybe I missed it among the many given solutions).
I would like to cover the case where an object is considered empty if all its values are undefined:
const isObjectEmpty = obj => Object.values(obj).every(val => typeof val === "undefined")
console.log(isObjectEmpty({})) // true
console.log(isObjectEmpty({ foo: undefined, bar: undefined })) // true
console.log(isObjectEmpty({ foo: false, bar: null })) // false
Example usage
Let's say, for the sake of example, you have a function (paintOnCanvas) that destructs values from its argument (x, y and size). If all of them are undefined, they are to be left out of the resulting set of options. If not they are not, all of them are included.
function paintOnCanvas ({ brush, x, y, size }) {
const baseOptions = { brush }
const areaOptions = { x, y, size }
const options = isObjectEmpty(areaOptions) ? baseOptions : { ...baseOptions, areaOptions }
// ...
}
I'll start off by stating that I don't know if this is possible at all, but I'm reading over the Kendo UI documentation and trying to figure out how to at least try it, but I'm running into a lot of difficulties with making a custom binding. This is a followup to another question I am still working on, which is posted here. If this is not an appropriate question, please kindly let me know, and I will close it or rephrase it. I'm just really lost and confused at this point.
As I understand it, based on what I've been told and tried, Kendo cannot bind to an Associative Array not because the data isn't good, but because it is an array of objects, each as a separate individual entity - under normal circumstances, an array would be a bit different and contain a length property, as well as some other functions in the array prototype that make iteration through it possible.
So I was trying to conjecture how to get around this. I succeeded in getting what I think was a workaround to function. I preface that with "think" because I'm still too inexperienced with Javascript to truly know the ramifications of doing it this way (performance, stability, etc)
Here is what I did;
kendo template
<script type="text/x-kendo-template" id="display-items-many">
# for(var key in data) { #
# if (data.hasOwnProperty(key) && data[key].hasOwnProperty("Id")) { #
<tr>
<td>
<strong>#= data[key].Id #</strong>
</td>
<td class="text-right">
<code>#= data[key].Total #</code>
</td>
</tr>
# } #
# } #
</script>
html
<table class="table borderless table-hover table-condensed" data-bind="source: Associative data-template="display-items-many">
</table>
Now to me, immediately off hand, this gave me the illusion of functioning. So I got to thinking a bit more on how to fix this ...
I want to create a new binding called repeat. The goal of this binding is as follows;
repeat the template for each instance of an object within the given root object that meets a given criteria
In my head, this would function like this;
<div data-template="repeater-sample" data-bind="repeat: Associative"></div>
<script type="text/x-kendo-template" id="repeater-sample">
<div> ${ data.Id }</div>
</script>
And the criteria would be a property simply called _associationKey. So the following would, in theory, work.
$.ajax({
// get data from server and such.
}).done(function(results){
// simple reference to the 'associative array' for easier to read code
var associative = results.AssociativeArray;
// this is a trait that everything in the 'associative array' should have to match
// this is purely, purely an example. Obviously you would use a more robust property
var match = "Id";
// go through the results and wire up the associative array objects
for(var key in associative ) {
if(associative.hasOwnProperty(key) && associative[key].hasOwnProperty(match)) {
associative[key]._associationKey = 10; // obviously an example value
}
}
// a watered down example implementation, obviously a real use would be more verbose
viewModel = kendo.observable({
// property = results.property
// property = results.property
associativeArray = associative
});
kendo.bind('body', viewModel);
});
So far this actually seems to work pretty well, but I have to hard code the logic in the template using inline scripting. That's kind of what I want to avoid.
Problem
The big issue is that I'm vastly confused on telerik's documentation for custom bindings (available here). I do have their examples to draw from, yes - but it's a bit confusing to me how it interacts with the object. I'll try to explain, but I'm so lost that it may be difficult.
This is what telerik gives for an example custom binding, and I've pruned it a bit for space concerns;
<script>
kendo.data.binders.repeater = kendo.data.Binder.extend({
init: function(element, bindings, options) {
//call the base constructor
kendo.data.Binder.fn.init.call(this, element, bindings, options);
var that = this;
// how do we interact with the data that was bound?
}
});
</script>
So essentially that's where I am lost. I'm having a big disconnect figuring out how to interact with the actual "associative array" that is bound using data-bind="repeat: associativeArray"
So ..
I need to interact with the bound data (the entire 'associative array')
I need to be able to tell it to render the target template for each instance that matches
Further Updates
I have been digging through the kendo source code, and this is what I have so far - by taking the source binding as an example... but I'm still not getting the right results. Unfortunately this poses a few problems;
some of the functions are internal to kendo, I'm not sure how to get access to them without re-writing them. While I have the source and can do that, I'd prefer to make version agnostic code so that it can "plug in" to newer releases
I'm totally lost about what a lot of this does. I basically made a copy of the source binding and replaced it with my own syntax where possible, since the concept is fundamentally the same. I cannot figure out where to do the test for qualification to be rendered, if that makes sense.
I'm having a big logic disconnect here - there should ideally be some place where I can basically say ... If the current item that kendo is attempting to render in a template matches a criteria, render it. If not, pass it over and then another place where I tell it to iterate over every object in the 'associative array' so as to get to the point where I test it.
I feel just forcing a for loop in here will actually make this fire too many times, and I am getting pretty lost. Any help is greatly appreciated.
kendo.data.binders.repeat = kendo.data.Binder.extend({
init: function(element, bindings, options) {
kendo.data.Binder.fn.init.call(this, element, bindings, options);
var source = this.bindings.repeat.get();
if (source instanceof kendo.data.DataSource && options.autoBind !== false) {
source.fetch();
}
},
refresh: function(e) {
var that = this,
source = that.bindings.repeat.get();
if (source instanceof kendo.data.ObservableArray|| source instanceof kendo.data.DataSource) {
e = e || {};
if (e.action == "add") {
that.add(e.index, e.items);
} else if (e.action == "remove") {
that.remove(e.index, e.items);
} else if (e.action != "itemchange") {
that.render();
}
} else {
that.render();
}
},
container: function() {
var element = this.element;
if (element.nodeName.toLowerCase() == "table") {
if (!element.tBodies[0]) {
element.appendChild(document.createElement("tbody"));
}
element = element.tBodies[0];
}
return element;
},
template: function() {
var options = this.options,
template = options.template,
nodeName = this.container().nodeName.toLowerCase();
if (!template) {
if (nodeName == "select") {
if (options.valueField || options.textField) {
template = kendo.format('<option value="#:{0}#">#:{1}#</option>',
options.valueField || options.textField, options.textField || options.valueField);
} else {
template = "<option>#:data#</option>";
}
} else if (nodeName == "tbody") {
template = "<tr><td>#:data#</td></tr>";
} else if (nodeName == "ul" || nodeName == "ol") {
template = "<li>#:data#</li>";
} else {
template = "#:data#";
}
template = kendo.template(template);
}
return template;
},
add: function(index, items) {
var element = this.container(),
parents,
idx,
length,
child,
clone = element.cloneNode(false),
reference = element.children[index];
$(clone).html(kendo.render(this.template(), items));
if (clone.children.length) {
parents = this.bindings.repeat._parents();
for (idx = 0, length = items.length; idx < length; idx++) {
child = clone.children[0];
element.insertBefore(child, reference || null);
bindElement(child, items[idx], this.options.roles, [items[idx]].concat(parents));
}
}
},
remove: function(index, items) {
var idx, element = this.container();
for (idx = 0; idx < items.length; idx++) {
var child = element.children[index];
unbindElementTree(child);
element.removeChild(child);
}
},
render: function() {
var source = this.bindings.repeat.get(),
parents,
idx,
length,
element = this.container(),
template = this.template();
if (source instanceof kendo.data.DataSource) {
source = source.view();
}
if (!(source instanceof kendo.data.ObservableArray) && toString.call(source) !== "[object Array]") {
source = [source];
}
if (this.bindings.template) {
unbindElementChildren(element);
$(element).html(this.bindings.template.render(source));
if (element.children.length) {
parents = this.bindings.repeat._parents();
for (idx = 0, length = source.length; idx < length; idx++) {
bindElement(element.children[idx], source[idx], this.options.roles, [source[idx]].concat(parents));
}
}
}
else {
$(element).html(kendo.render(template, source));
}
}
});
I would propose as a simpler solution transform transmitted associative array in an array. This is pretty simple and (for most cases) can solve your problem.
Lets say that you get the following associative array received from the server:
{
"One" : { Name: "One", Id: "id/one" },
"Two" : { Name: "Two", Id: "id/two" },
"Three" : { Name: "Three", Id: "id/three" }
}
That is store in a variable called input. Transform it from associative to no associative is as easy as:
var output = [];
$.each(input, function(idx, elem) {
elem.index = idx;
output.push(elem);
});
Now, you have in output an equivalent array where I saved the index field into a field called index for each element of the associative array.
Now you can use out-of-the-box code for displaying the data received from the server.
See it in action here : http://jsfiddle.net/OnaBai/AGfWc/
You can even use KendoUI DataSource for retrieving and transforming the data by using DataSource.schema.parse method as:
var dataSource = new kendo.data.DataSource({
transport: {
read: ...
},
schema : {
parse: function (response) {
var output = [];
$.each(response, function(idx, elem) {
elem.index = idx;
output.push(elem);
});
return output;
}
}
});
and your model would be:
var viewModel = new kendo.data.ObservableObject({
Id: "test/id",
Associative: dataSource
});
You can see it in action here: http://jsfiddle.net/OnaBai/AGfWc/1/