js格式化时间

Date.prototype.pattern=function(fmt) {       
     var o = {        
     "M+" : this.getMonth()+1, //月份       
     "d+" : this.getDate(), //日       
     "h+" : this.getHours() == 0 ? 12 : this.getHours(), //小时       
     "H+" : this.getHours(), //小时       
     "m+" : this.getMinutes(), //分       
     "s+" : this.getSeconds(), //秒       
     "q+" : Math.floor((this.getMonth()+3)/3), //季度       
     "S" : this.getMilliseconds() //毫秒       
     };       
     var week = {       
     "0" : "\u65e5",       
     "1" : "\u4e00",       
     "2" : "\u4e8c",       
     "3" : "\u4e09",       
     "4" : "\u56db",       
     "5" : "\u4e94",       
     "6" : "\u516d"      
     };       
     if(/(y+)/.test(fmt)){       
         fmt=fmt.replace(RegExp.$1, (this.getFullYear()+"").substr(4 - RegExp.$1.length));       
     }       
     if(/(E+)/.test(fmt)){       
         fmt=fmt.replace(RegExp.$1, ((RegExp.$1.length>1) ? (RegExp.$1.length>2 ? "\u661f\u671f" : "\u5468") : "")+week[this.getDay()+""]);       
     }       
     for(var k in o){       
         if(new RegExp("("+ k +")").test(fmt)){       
             fmt = fmt.replace(RegExp.$1, (RegExp.$1.length==1) ? (o[k]) : (("00"+ o[k]).substr((""+ o[k]).length)));       
         }       
     }       
     return fmt;       
  }  
  var date = new Date();    
   window.alert(date.pattern("yyyy-MM-dd hh:mm:ss"));