将毫秒转成指定的日期格式

var format = function(date, format){
      var t = new Date(date);
      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;
          }
      })
  }

远行结果：2015-05-21