背景
日期格式化是编程中最常用的功能之一，C#中的日期格式化功能做的相当强大，方便易用，但JavaScript中却很不给力，也有网友给出了日期格式化方法：http://www.cnblogs.com/donghongtao/archive/2010/01/07/1641145.html，但用起来仍不方便。刚才看到博问中的一个问题(求一JS日期格式化函数，最好跟C#中的使用方法类似)，于是就把自己写的一个日期格式化方法分享给大家，欢迎拍砖。
方法代码
原理就是重写Date的toString方法(跟C#保持一致)，对传入的格式化参数内的内容进行替换，代码如下：
Date.prototype.toString=function(format,loc){ var time={}; time.Year=this.getFullYear(); time.TYear=(""+time.Year).substr(2); time.Month=this.getMonth()+1; time.TMonth=time.Month<10?"0"+time.Month:time.Month; time.Day=this.getDate(); time.TDay=time.Day<10?"0"+time.Day:time.Day; time.Hour=this.getHours(); time.THour=time.Hour<10?"0"+time.Hour:time.Hour; time.hour=time.Hour<13?time.Hour:time.Hour-12; time.Thour=time.hour<10?"0"+time.hour:time.hour; time.Minute=this.getMinutes(); time.TMinute=time.Minute<10?"0"+time.Minute:time.Minute; time.Second=this.getSeconds(); time.TSecond=time.Second<10?"0"+time.Second:time.Second; time.Millisecond=this.getMilliseconds(); time.Week=this.getDay(); var MMMArrEn=["Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"]; var MMMArr=["一月","二月","三月","四月","五月","六月","七月","八月","九月","十月","十一月","十二月"]; var WeekArrEn=["Sun","Mon","Tue","Web","Thu","Fri","Sat"]; var WeekArr=["星期日","星期一","星期二","星期三","星期四","星期五","星期六"]; var oNumber=time.Millisecond/1000; if(format!=undefined && format.replace(/\s/g,"").length>0){ if(loc!=undefined && loc =="en"){ MMMArr=MMMArrEn.slice(0); WeekArr=WeekArrEn.slice(0); } format=format .replace(/yyyy/ig,time.Year) .replace(/yyy/ig,time.Year) .replace(/yy/ig,time.TYear) .replace(/y/ig,time.TYear) .replace(/MMM/g,MMMArr[time.Month-1]) .replace(/MM/g,time.TMonth) .replace(/M/g,time.Month) .replace(/dd/ig,time.TDay) .replace(/d/ig,time.Day) .replace(/HH/g,time.THour) .replace(/H/g,time.Hour) .replace(/hh/g,time.Thour) .replace(/h/g,time.hour) .replace(/mm/g,time.TMinute) .replace(/m/g,time.Minute) .replace(/ss/ig,time.TSecond) .replace(/s/ig,time.Second) .replace(/fff/ig,time.Millisecond) .replace(/ff/ig,oNumber.toFixed(2)*100) .replace(/f/ig,oNumber.toFixed(1)*10) .replace(/EEE/g,WeekArr[time.Week]); } else{ format=time.Year+"-"+time.Month+"-"+time.Day+" "+time.Hour+":"+time.Minute+":"+time.Second; } return format; } var d=new Date(); console.log(d.toString()); //2011-12-29 11:29:43 console.log(d.toString("")); //2011-12-29 11:29:43 console.log(d.toString("yyyy-MM-dd")); //2011-12-29 console.log(d.toString("HH:mm:ss")); //11:29:43 console.log(d.toString("yyyy-MM-dd HH:mm:ss")); //2011-12-29 11:29:43 console.log(d.toString("yyyy年MM月dd日 HH:mm:ss")); //2011年12月29日 11:29:43 console.log(d.toString("yyyy-MM-dd HH:mm:ss fff")); //2011-12-29 11:29:43 862
代码中TMonth、TDay前的T表示两位数(Two)。
小结
本人是javascript初学者，欢迎大家讨论拍砖。