form序列化为json对象，过滤空值

serializeJson: function (obj) {
    var serializeObj = {};
    var array = $(obj).serializeArray();
    var str = $(obj).serialize();
    $(array).each(function () {
        if (undefined != this.value && '' != this.value) {
            if (serializeObj[this.name]) {
                if ($.isArray(serializeObj[this.name])) {
                    serializeObj[this.name].push(this.value);
                } else {
                    serializeObj[this.name] = [serializeObj[this.name], this.value];
                }
            } else {
                serializeObj[this.name] = this.value;
            }
        }
    });
    return serializeObj;
},