form表单数据进行json转换

$.fn.serializeJson = 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;
};