Я адаптировал JavaScript serialize функцию, написанную Kevin van Zonneveld, для использования с jQuery. Serialize работает также как и одноименная функция в PHP. Она хорошо выручит Вас, если Вы захотите передать в AJAX запросе Объект (JavaScript object).

Пример использования: my_data = $.serialize({data: 'value'});

Код:

jQuery.extend({
   serialize: function ( mixed_value ) {
       // Returns a string representation of variable (which can later be unserialized)
       //
       // version: 906.1807
       // discuss at: http://phpjs.org/functions/serialize
       // +   original by: Arpad Ray (mailto:arpad@php.net)
       // +   improved by: Dino
       // +   bugfixed by: Andrej Pavlovic
       // +   bugfixed by: Garagoth
       // +      input by: DtTvB (http://dt.in.th/2008-09-16.string-length-in-bytes.html)
       // +   bugfixed by: Russell Walker (http://www.nbill.co.uk/)
       // %          note: We feel the main purpose of this function should be to ease the transport of data between php & js
       // %          note: Aiming for PHP-compatibility, we have to translate objects to arrays
       // *     example 1: serialize(['Kevin', 'van', 'Zonneveld']);
       // *     returns 1: 'a:3:{i:0;s:5:"Kevin";i:1;s:3:"van";i:2;s:9:"Zonneveld";}'
       // *     example 2: serialize({firstName: 'Kevin', midName: 'van', surName: 'Zonneveld'});
       // *     returns 2: 'a:3:{s:9:"firstName";s:5:"Kevin";s:7:"midName";s:3:"van";s:7:"surName";s:9:"Zonneveld";}'
       var _getType = function( inp ) {
           var type = typeof inp, match;
           var key;
           if (type == 'object' && !inp) {
               return 'null';
           }
           if (type == "object") {
               if (!inp.constructor) {
                   return 'object';
               }
               var cons = inp.constructor.toString();
               match = cons.match(/(\w+)\(/);
               if (match) {
                   cons = match[1].toLowerCase();
               }
               var types = ["boolean", "number", "string", "array"];
               for (key in types) {
                   if (cons == types[key]) {
                       type = types[key];
                       break;
                   }
               }
           }
           return type;
       };
       var type = _getType(mixed_value);
       var val, ktype = '';

       switch (type) {
           case "function":
               val = "";
               break;
           case "boolean":
               val = "b:" + (mixed_value ? "1" : "0");
               break;
           case "number":
               val = (Math.round(mixed_value) == mixed_value ? "i" : "d") + ":" + mixed_value;
               break;
           case "string":
               val = "s:" + encodeURIComponent(mixed_value).replace(/%../g, 'x').length + ":\"" + mixed_value + "\"";
               break;
           case "array":
           case "object":
               val = "a";
               /*
               if (type == "object") {
                   var objname = mixed_value.constructor.toString().match(/(\w+)\(\)/);
                   if (objname == undefined) {
                       return;
                   }
                   objname[1] = serialize(objname[1]);
                   val = "O" + objname[1].substring(1, objname[1].length - 1);
               }
               */
               var count = 0;
               var vals = "";
               var okey;
               var key;
               for (key in mixed_value) {
                   ktype = _getType(mixed_value[key]);
                   if (ktype == "function") {
                       continue;
                   }

                   okey = (key.match(/^[0-9]+$/) ? parseInt(key, 10) : key);
                   vals += $.serialize(okey) +
                           $.serialize(mixed_value[key]);
                   count++;
               }
               val += ":" + count + ":{" + vals + "}";
               break;
           case "undefined": // Fall-through
           default: // if the JS object has a property which contains a null value, the string cannot be unserialized by PHP
               val = "N";
               break;
       }
       if (type != "object" && type != "array") {
           val += ";";
       }
       return val;
   }
});

Оригинал и последняя версия в моём блоге.