Is there javascript (prefer jquery) library that automatically maps form elements to JSON?

Question

Background: This is something I have been looking for since before even JSON was known as JSON.

Suppose you have the following javascript variable inside your code:

jsonroot = 
{
    'fname':'valued'
    ,'lname':'customer'
    ,faves:['berry','chocolate','mint']
    ,actors:[
        {'fname':'brad','lname':'pitt'}
        ,{'fname':'mike','lname':'hammer'}
    ]
};

You can easily see how this maps to JSON, it is a 1:1 correspondence.

Question: Is there a library that can take this 1:1 correspondence and carry it over to HTML Form elements? For example, I would like to do something like this inside a FORM element:

<input type="text" mapping="jsonroot['fname']" id="fname"></input>
<input type="text" mapping="jsonroot['lname']" id="lname"></input>

<legend>
    <fieldset>Favorite Flavors</fieldset>
    <input type="text" mapping="jsonroot['faves'][0]" id="fave_0"></input>
    <input type="text" mapping="jsonroot['faves'][1]" id="fave_1"></input>
    <input type="text" mapping="jsonroot['faves'][2]" id="fave_2"></input>
</legend>

<legend>
    <fieldset>Favorite Actors</fieldset>
    <input type="text" mapping="jsonroot['actors'][0]['fname']" id="fave_0_fname"></input>
    <input type="text" mapping="jsonroot['actors'][0]['lname']" id="fave_0_lname"></input>

    <input type="text" mapping="jsonroot['actors'][1]['fname']" id="fave_1_fname"></input>
    <input type="text" mapping="jsonroot['actors'][1]['lname']" id="fave_1_lname"></input>
</legend>

Rationale: Sometimes, instead of submitting form variables via POST or GET, I want to pass them into a javascript variable, then do something with the variable, and then send it somewhere.

Writing the HTML Form <-> JSON translation is tedious. I can't be the only person out there who has wanted to to this, so is there a library that handles this automatically?

Answer 1

Use something like Mark Gibson's JSON JQuery plugin. It adds $.toJSON() and $.parseJSON() methods. Use this in combination with code that serializes a form to an object such as Serialize Form to JSON:

$.fn.serializeObject = function()
{
   var o = {};
   var a = this.serializeArray();
   $.each(a, function() {
       if (o[this.name]) {
           if (!o[this.name].push) {
               o[this.name] = [o[this.name]];
           }
           o[this.name].push(this.value || '');
       } else {
           o[this.name] = this.value || '';
       }
   });
   return o;
};