php 获取 今天是星期几

<?php
/*判断当天是星期几*/
$weekarray=array("日","一","二","三","四","五","六"); //先定义一个数组
$yi="星期一";
$er="星期二";
$san="星期三";
$si="星期四";
$wu="星期五";
$liu="星期六";
$ri="星期日";
$ji="星期".$weekarray[date("w")];