radio实现第一次点击选中第二次点击取消

Jquery代码如下：

$("#add_form .radio input").bind("click",function(){
 	var $radio = $(this);
    // if this was previously checked
    if ($radio.data('waschecked') == true)
    {
        $radio.prop('checked', false);
        $radio.data('waschecked', false);
    }
    else
    {
         $radio.prop('checked', true);
         $radio.data('waschecked', true);
    }
    // remove was checked from other radios
    $radio.siblings('input[type="radio"]').data('waschecked', false);
});