收集的几个javascript的date和array扩展

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;
	}

Array.prototype.del=function(n) {
　if(n<0)
	return this;
  else
 	return this.slice(0,n).concat(this.slice(n+1,this.length));
}