How can I convert query string or JSON object map to single JSON object with jQuery?

You can try this

String.prototype.QueryStringToJSON = function () {href = this;qStr = href.replace(/(.*?\?)/, '');qArr = qStr.split('&');stack = {};for (var i in qArr) {    var a = qArr[i].split('=');    var name = a[0],        value = isNaN(a[1]) ? a[1] : parseFloat(a[1]);    if (name.match(/(.*?)\[(.*?)]/)) {        name = RegExp.$1;        name2 = RegExp.$2;        //alert(RegExp.$2)        if (name2) {            if (!(name in stack)) {                stack[name] = {};            }            stack[name][name2] = value;        } else {            if (!(name in stack)) {                stack[name] = [];            }            stack[name].push(value);        }    } else {        stack[name] = value;    }}return stack;}

Query String

    href="j.html?name=nayan&age=29&salary=20000&interest[]=php&interest[]=jquery&interest[1]=python&interest[2]=Csharp&fan[friend]=rangan&fan[family]=sujan&sports[1]=cricket&sports[2]=football";

usage

alert(href.QueryStringToJSON().toSource())

output

({name:"nayan", age:29, salary:20000, interest:["php", "python", "Csharp"], fan:{friend:"rangan", family:"sujan"}, sports:{1:"cricket", 2:"football"}})

kgiannakakis's suggestion to traverse the map was a good starting point, though I don't feel that it qualifies as an answer to my original question. After a couple of hours of head banging, I settled for this, which allows you to serialize elements based on a custom attribute (I didn't want to settle for having to use the 'name' attribute on my form elements, which jQuery requires). I have also started using the JSON library from json.org in order to stringify the object I create. The serializeToJSON function of my plugin is what I was looking for as an answer to my question, the rest is just exta.

Note: This is for a client, so the 'CustomXXX' names and attributes were substituted in for what they actually are

jQuery.fn.extend({    serializeCustomPropertyArray: function() {        return this.map(function() {            return this.elements ? jQuery.makeArray(this.elements) : this;        }).filter(function() {            return jQuery(this).attr('CustomAttribute') &&                (this.checked || /select|textarea/i.test(this.nodeName) ||                        /text|hidden|password|search/i.test(this.type));        }).map(function(i, elem) {            var val = jQuery(this).val();            return val == null ? null : jQuery.isArray(val) ?                jQuery.map(val, function(val, i) {                    return { name: jQuery(elem).attr('CustomAttribute'), value: val };                }) : { name: jQuery(elem).attr('CustomAttribute'), value: val };        }).get();    },    serializeToJSON: function() {        var objectMap = this.serializeCustomPropertyArray();        var objectJson = new Object;        jQuery.each(objectMap, function() {            objectJson[this.name] = (this.value !== null) ? this.value : 'null';        });        return JSON.stringify(objectJson);    }});

This can be called like:

$('#fields').find(':input[CustomGroup="Months"]').serializeToJSON();

Assuming your document looks something like:

<div id="fields">   <input type="checkbox" CustomGroup="Months" CustomAttribute="January" />January<br />   <input type="checkbox" CustomGroup="Months" CustomAttribute="February" />February<br />   ...</div>

The JSON that's built looks like:

{ January: 'on', February: 'on', ... }

You can traverse an object map using the $.each utility function.

$(function() {    map = [{ January: 'on' },{ March: 'on' },{ September: 'on' }];    $.each(map, function() {       $.each(this, function(key, val) {alert(key + " = " + val);});;    });});

The first each gets you all array objects. With the second one you can get the key and value of your object.