数字转成汉字表示

//数字转成汉字表示

Number.prototype.toCn=function(){
　　var arrs=["零","一","二","三","四","五","六","七","八","九"];
　　var arrt=["","十","百","千","万","亿"];
　　var arr=[];
　　var unit=-1;
　　var _this=this;
　　while(_this!=0){
　　　　arr.unshift(arrt[unit++]);
　　　　var number=_this%10;
　　　　arr.unshift(arrs[number]);
　　　　_this=Math.floor(_this/10);
　　}
　　return arr.join('');
}
alert(new Number(12005).toCn());