js 獲取url字符串中指定參數值

<script type="text/javascript">
	var url = "http://www.t.com?c=222&id=1s211113&w=1";
	console.log(getvar(url,"id"));
	
	function getvar(url,par){
		var urlsearch = url.split('?');
		pstr = urlsearch[1].split('&');
		for (var i = pstr.length - 1; i >= 0; i--) {
			var tep = pstr[i].split("=");
			if(tep[0] == par){
				return tep[1];
			}
		}
		return(false);
	}	
</script>