$('<div><input name="a" value="a" /></div>').to_json()
  //=> {a: 'a'}
$('<div><input name="a.b" value="b" /></div>').to_json()
  //=> {a: {b: 'b'}}
$('<div><input name="a.b[]" value="1" /><input name="a.b[]" value="2" /></div>').to_json()
  //=> {a: {b: ['1', '2']}}

插件下载地址：https://raw.github.com/benz303/jQuery.fn.to_json/gh-pages/jQuery.fn.to_json.js

Github 地址：http://benz303.github.com/jQuery.fn.to_json/