获取星期方法

function get_week($date)
{
    //强制转换日期格式
    $date_str = date('Y-m-d', strtotime($date));
    //封装成数组
    $arr = explode("-", $date_str);

    //参数赋值
    //年
    $year = $arr[0];

    //月，输出2位整型，不够2位右对齐
    $month = sprintf('%02d', $arr[1]);

    //日，输出2位整型，不够2位右对齐
    $day = sprintf('%02d', $arr[2]);

    //时分秒默认赋值为0；
    $hour = $minute = $second = 0;

    //转换成时间戳
    $strap = mktime($hour, $minute, $second, $month, $day, $year);

    //获取数字型星期几
    $number_wk = date("w", $strap);

    //自定义星期数组
    $weekArr = array("0", "1", "2", "3", "4", "5", "6");

    //获取数字对应的星期
    return $weekArr[$number_wk];
}