form to json with nested fields

formjson.js

$.fn.formJSON = function(){
	var fields			= $(this).serializeArray(),
		json			= {},
		arraynames		= {};
	for( var v = 0; v < fields.length; v++){
		var field 		= fields[v],
			name 		= field.name.replace(/\]/gi,'').split('['),
			value 		= field.value,
			lineconf 	= {};
		for(var i = name.length-1; i >= 0; i--){
			var nestname = name[i];
			if(nestname.length === 0){
				if( typeof arraynames[name[i-1]] === 'undefined'){
					arraynames[name[i-1]] = 0;
				}else{
					arraynames[name[i-1]] += 1;
				}
				nestname = arraynames[name[i-1]];
			}
			if(i === name.length-1){
				if( value === 'true' ){
					value = true;
				}else if( value === 'false' ){
					value = false;
				}else if( !isNaN( parseFloat( value ) ) ){
					value = parseFloat( value );
				}
				lineconf[nestname] = value;
			}else{
				var newobj = lineconf;
				lineconf = {};
				lineconf[nestname] = newobj;
			}		
		}
		$.extend(true, json, lineconf);
	};
	return json;
}

Converts a form to JSON.
See Example
Works with nested names name="data[value][]".
It's not perfect since array fields [] becomes an object {"0","value"} rather than["value"]`, but at 38 lines of code, it's pretty effective and fast.