php 简单笔记

1、时间

$date1 = "2014-11-11";
echo date('Y-m-d',strtotime("$date1 +5 day"));  //输出结果：2014-11-16
//相应地,要增加月,年,将day改成month或year即可

//+++ 今天、昨天、明天 、上一周、下一周 +++++++++
echo "今天:",date("Y-m-d",time()),"<hr>";
echo "昨天:",date("Y-m-d",strtotime("-1 day")), "<hr>";
echo "明天:",date("Y-m-d",strtotime("+1 day")), "<hr>";
echo "一周后:",date("Y-m-d",strtotime("+1 week")), "<hr>";
echo "一周零两天四小时两秒后:",date("Y-m-d G:H:s",strtotime("+1 week 2 days 4 hours 2 seconds")), "<hr>";
echo "下个星期四:",date("Y-m-d",strtotime("next Thursday")), "<hr>";
echo "上个周一:".date("Y-m-d",strtotime("last Monday"))."<hr>";
echo "一个月前:".date("Y-m-d",strtotime("last month"))."<hr>";
echo "一个月后:".date("Y-m-d",strtotime("+1 month"))."<hr>";
echo "十年后:".date("Y-m-d",strtotime("+10 year"))."<hr>"; 

2、日期格式化输出

 $var=sprintf("%04d", 2);//生成4位数，不足前面补0
 echo $var;//结果为0002