JS 将中国标准时间转化为指定格式时间

var format = function(time, format){
var t = new Date(time);
var tf = function(i){return (i < 10 ? '0' : '') + i};
return format.replace(/yyyy|MM|dd|HH|mm|ss/g, function(a){
  switch(a){
             case 'yyyy':
                 return tf(t.getFullYear());
                 break;
             case 'MM':
                 return tf(t.getMonth() + 1);
                 break;
             case 'mm':
                 return tf(t.getMinutes());
                 break;
             case 'dd':
                 return tf(t.getDate());
                 break;
             case 'HH':
                 return tf(t.getHours());
                 break;
             case 'ss':
                 return tf(t.getSeconds());
                 break;
      }
 });
} 

如：format(data.birthday, 'yyyy-MM-dd')