标签：php

<?php
// 加密：
function string_secret($string)
{
    $key = "yadgen";

    //密锁串，不能出现重复字符，内有A-Z,a-z,0-9,/,=,+,_,
    $lockstream = 'st=lDEFABCNOPyzghi_jQRST-UwxkVWXYZabcdef+IJK6/7nopqr89LMmGH012345uv';
    //随机找一个数字，并从密锁串中找到一个密锁值
    $lockLen = strlen($lockstream);
    $lockCount = rand(0,$lockLen-1);
    $randomLock = $lockstream[$lockCount];
    //结合随机密锁值生成MD5后的密码
    $password = md5($key.$randomLock);
    //开始对字符串加密
    $txtStream = base64_encode($string);
    $tmpStream = '';
    $i=0;$j=0;$k = 0;
    for ($i=0; $i<strlen($txtStream); $i++) {
        $k = ($k == strlen($password)) ? 0 : $k;
        $j = (strpos($lockstream,$txtStream[$i])+$lockCount+ord($password[$k]))%($lockLen);
        $tmpStream .= $lockstream[$j];
        $k++;
    }
    return $tmpStream.$randomLock;
}

// 解密：
function secret_string($string)
{
    $key = "yadgen";

    //密锁串，不能出现重复字符，内有A-Z,a-z,0-9,/,=,+,_,
    $lockstream = 'st=lDEFABCNOPyzghi_jQRST-UwxkVWXYZabcdef+IJK6/7nopqr89LMmGH012345uv';

    $lockLen = strlen($lockstream);
    //获得字符串长度
    $txtLen = strlen($string);
    //截取随机密锁值
    $randomLock = $string[$txtLen - 1];
    //获得随机密码值的位置
    $lockCount = strpos($lockstream,$randomLock);
    //结合随机密锁值生成MD5后的密码
    $password = md5($key.$randomLock);
    //开始对字符串解密
    $txtStream = substr($string,0,$txtLen-1);
    $tmpStream = '';
    $i=0;$j=0;$k = 0;
    for($i=0; $i<strlen($txtStream); $i++){
        $k = ($k == strlen($password)) ? 0 : $k;
        $j = strpos($lockstream,$txtStream[$i]) - $lockCount - ord($password[$k]);
        while($j < 0){
            $j = $j + ($lockLen);
        }
        $tmpStream .= $lockstream[$j];
        $k++;
    }
    return base64_decode($tmpStream);
}
?>

 

<?php
function tranTime($time) {
    $rtime = date("m-d H:i",$time);
    $rtime2 = date("Y-m-d H:i",$time);
    $htime = date("H:i",$time);
    $time = time() - $time;
    if ($time < 60) {
        $str = '刚刚';
    } elseif ($time < 60 * 60) {
        $min = floor($time/60);
        $str = $min.' 分钟前';
    } elseif ($time < 60 * 60 * 24) {
        $h = floor($time/(60*60));
        $str = $h.'小时前 '.$htime;
    } elseif ($time < 60 * 60 * 24 * 3) {
        $d = floor($time/(60*60*24));
        if($d==1)
           $str = '昨天 '.$htime;
        else
           $str = '前天 '.$htime;
    } elseif ($time < 60 * 60 * 24 * 7) {
        $d = floor($time/(60*60*24));
           $str = $d.' 天前 '.$htime;
    } elseif ($time < 60 * 60 * 24 * 30) {
        $str = $rtime;
    } else {
        $str = $rtime2;
    }
    return $str;
}
$w_time = time() - 3600;
$times = tranTime($w_time);
echo $times;
?>

 

<?php
function get_week($year) { 
    $year_start = $year . "-01-01"; 
    $year_end = $year . "-12-31"; 
    $startday = strtotime($year_start); 
    if (intval(date('N', $startday)) != '1') { 
        $startday = strtotime("next monday", strtotime($year_start)); //获取年第一周的日期 
    } 
    $year_mondy = date("Y-m-d", $startday); //获取年第一周的日期 
 
    $endday = strtotime($year_end); 
    if (intval(date('W', $endday)) == '7') { 
        $endday = strtotime("last sunday", strtotime($year_end)); 
    } 
 
    $num = intval(date('W', $endday)); 
    for ($i = 1; $i <= $num; $i++) { 
        $j = $i -1; 
        $start_date = date("Y-m-d", strtotime("$year_mondy $j week ")); 
 
        $end_day = date("Y-m-d", strtotime("$start_date +6 day")); 
 
        $week_array[$i] = array ( 
            str_replace("-", 
            ".", 
            $start_date 
        ), str_replace("-", ".", $end_day)); 
    } 
    return $week_array; 
}
?>

函数get_week()通过传入参数$year年份，获取当年第一天和最后一天所在的周数，计算第一周的日期，通过循环获取每一周的第一天和最后一天的日期。最后返回是一个数组。
想得到指定周数的开始日期和结束日期，比如2011年第18周的开始日期和结束日期，代码如下：

<?php
$weeks = get_week(2011); 
echo '第18周开始日期：'.$weeks[18][0].''; 
echo '第18周结束日期：'.$weeks[18][1]; 
?>

最后输出结果：

第18周开始日期：2011.05.02 
第18周结束日期：2011.05.08

原文链接：http://www.helloweba.com/view-blog-125.html

<?php
$time = time();
$first_day = strtotime(date('Y-m-01', $time));
$last_day = strtotime(date('Y-m-d', strtotime("$first_day +1 month -1 day")));
?>