JS 和 PHP 获取某月的第一天和最后一天

PHP

//获取本月第一天和最后一天
$today=date("Y-m-d");
//直接把第一天设为1号，简单粗暴
$firstday = date('Y-m-01', strtotime($today)); 
$lastday = date('Y-m-d', strtotime("$firstday +1 month -1 day")); 
echo $firstday;
echo $lastday;

Javascript

var today = new Date();
var year = today.getFullYear();
//同上，直接设为1日。
var month = today.getMonth() + 1;
var   firstday = year + '-' + month + '-01';
var  day = new Date(year,month,0);
var lastday = year + '-' + month + '-' + day.getDate();//获取当月最后一天日期
alert(firstday+" and "+lastday);