PHP method to get last week, this week, last month, this month, this quarter, and last quarter time

开发过程中，常用日期处理函数，时间戳处理函数等，如下讲解：
<?php
echo date(&#39;Y-m-d h:i:s&#39;,time());

//运行结果(年月日时分秒，“-”间隔)：2014-09-12 06:28:32

echo date(&#39;Y-m-d&#39;,time());

//运行结果(年月日，“-”间隔)：2014-09-12

echo date(&#39;Y-m-d&#39;,strtotime(date(&#39;Y-m-d&#39;, time()-86400)));

//运行结果(当前日期前一天的年月日，“-”间隔)：2014-09-11

echo date(&#39;Ymd&#39;,time());

//运行结果(年月日，无间隔)：20140912

echo date(&#39;m-d&#39;,time());

//运行结果(月日，“-”间隔)：09-12

echo str_replace("-","月",date(&#39;m-d&#39;,time()-date(&#39;w&#39;,time())*86400))."日";

//运行结果(月日，汉字显示间隔)：09月12日

echo date(&#39;w&#39;,time());

//运行结果(星期几)：5

echo time();

//运行结果(当前日期时间的秒数)：1410503809

echo strtotime(date(&#39;Y-m-d&#39;,time()));

//运行结果(当前日期秒数，具体到天)：1410503809

echo date(&#39;Y-m-d&#39;,strtotime(date(&#39;Y-m-d&#39;, time()))-date(&#39;w&#39;,strtotime(date(&#39;Y-m-d&#39;, time())))*86400);

//运行结果(当前日期所属自然周的起始日期即周日的日期，具体到天，“-”间隔)：2014-09-07

//php获取今日开始时间戳和结束时间戳

$beginToday=mktime(0,0,0,date('m'),date('d'),date('Y'));

$endToday=mktime(0,0,0,date('m'),date('d')+1,date('Y'))-1;

//php获取昨日起始时间戳和结束时间戳

$beginYesterday=mktime(0,0,0,date('m'),date('d')-1,date('Y'));

$endYesterday=mktime(0,0,0,date('m'),date('d'),date('Y'))-1;

//php获取上周起始时间戳和结束时间戳

$beginLastweek=mktime(0,0,0,date('m'),date('d')-date('w')+1-7,date('Y'));

$endLastweek=mktime(23,59,59,date('m'),date('d')-date('w')+7-7,date('Y'));

//php获取本月起始时间戳和结束时间戳

$beginThismonth=mktime(0,0,0,date('m'),1,date('Y'));

$endThismonth=mktime(23,59,59,date('m'),date('t'),date('Y'));

<?php
    /**date 2015-04-11
     * author http://www.lai18.com
     **/
    echo date("Ymd",strtotime("now")), "\n";
    echo date("Ymd",strtotime("-1 week Monday")), "\n";
    echo date("Ymd",strtotime("-1 week Sunday")), "\n";
    echo date("Ymd",strtotime("+0 week Monday")), "\n";
    echo date("Ymd",strtotime("+0 week Sunday")), "\n";

    echo "*********第几个月:";
    echo date(&#39;n&#39;);
    echo "*********本周周几:";
    echo date("w");
    echo "*********本月天数:";
    echo date("t");
    echo "*********";

    echo &#39;<br>上周起始时间:<br>&#39;;
    echo date("Y-m-d H:i:s",mktime(0, 0 , 0,date("m"),date("d")-date("w")+1-7,date("Y"))),"\n";
    echo date("Y-m-d H:i:s",mktime(23,59,59,date("m"),date("d")-date("w")+7-7,date("Y"))),"\n";
    echo &#39;<br>本周起始时间:<br>&#39;;
    echo date("Y-m-d H:i:s",mktime(0, 0 , 0,date("m"),date("d")-date("w")+1,date("Y"))),"\n";
    echo date("Y-m-d H:i:s",mktime(23,59,59,date("m"),date("d")-date("w")+7,date("Y"))),"\n";

    echo &#39;<br>上月起始时间:<br>&#39;;
    echo date("Y-m-d H:i:s",mktime(0, 0 , 0,date("m")-1,1,date("Y"))),"\n";
    echo date("Y-m-d H:i:s",mktime(23,59,59,date("m") ,0,date("Y"))),"\n";
    echo &#39;<br>本月起始时间:<br>&#39;;
    echo date("Y-m-d H:i:s",mktime(0, 0 , 0,date("m"),1,date("Y"))),"\n";
    echo date("Y-m-d H:i:s",mktime(23,59,59,date("m"),date("t"),date("Y"))),"\n";

    $season = ceil((date(&#39;n&#39;))/3);//当月是第几季度
    echo &#39;<br>本季度起始时间:<br>&#39;;
    echo date(&#39;Y-m-d H:i:s&#39;, mktime(0, 0, 0,$season*3-3+1,1,date(&#39;Y&#39;))),"\n";
    echo date(&#39;Y-m-d H:i:s&#39;, mktime(23,59,59,$season*3,date(&#39;t&#39;,mktime(0, 0 , 0,$season*3,1,date("Y"))),date(&#39;Y&#39;))),"\n";

    $season = ceil((date(&#39;n&#39;))/3)-1;//上季度是第几季度
    echo &#39;<br>上季度起始时间:<br>&#39;;
    echo date(&#39;Y-m-d H:i:s&#39;, mktime(0, 0, 0,$season*3-3+1,1,date(&#39;Y&#39;))),"\n";
    echo date(&#39;Y-m-d H:i:s&#39;, mktime(23,59,59,$season*3,date(&#39;t&#39;,mktime(0, 0 , 0,$season*3,1,date("Y"))),date(&#39;Y&#39;))),"\n";
?>