JS实现日期格式化

Date.prototype.format = function(format) {      var o = {   "M+" : this.getMonth() + 1, //month    "d+" : this.getDate(), //day    "h+" : this.getHours(), //hour    "m+" : this.getMinutes(), //minute    "s+" : this.getSeconds(), //second    "q+" : Math.floor((this.getMonth() + 3) / 3), //quarter    "S" : this.getMilliseconds()   //millisecond    }   if (/(y+)/.test(format)) {       format = format.replace(RegExp.$1, (this.getFullYear() + "").substr(4 - RegExp.$1.length));   }     for ( var k in o) {       if (new RegExp("(" + k + ")").test(format)) {    format = format.replace(RegExp.$1, RegExp.$1.length == 1 ? o[k] : ("00" + o[k]).substr(("" + o[k]).length));       }   }   return format;  }    //调用过程  function operation(value) {      var date = new Date(value);// 或者直接new Date();      return date.format("yyyy-MM-dd hh:mm:ss");  }