PHP

DateTime

//拿現在時間
$dt = new \DateTime('NOW');
//拿月初 2022-07-01 00:00:00
$dateStart = $dt->format('Y-m-01 00:00:00');
//拿月底 2022-07-31 23:59:59
$dateEnd = $dt->format('Y-m-t 23:59:59');
//拿上個月月初
$dateStart = date('Y-m-01 00:00:00', strtotime('-1 month'));
//拿上個月月底
$dateEnd = date('Y-m-t 23:59:59', strtotime($dateStart));

//日期轉成星期幾
$day = DayOfWeekToChineseDay(date('w', strtotime($dateStart)));
$dateStartShow = date("Y-m-d({$day}) H:i:s", strtotime($dateStart));
    
function DayOfWeekToChineseDay($day)
{
    switch ($day) {
        case "0":
            return "日";
        case "1":
            return "一";
        case "2":
            return "二";
        case "3":
            return "三";
        case "4":
            return "四";
        case "5":
            return "五";
        case "6":
            return "六";
    }
}

密碼驗證

// 線上生成的都用這個，很好用
// https://phppasswordhash.com/
// 產生PWD
password_hash($pwd, PASSWORD_DEFAULT)
// 驗證用
password_verify($pwd, $hash)，正確回傳true
if (!password_verify($pwd, $hash))
    throw new Exception("錯誤");

Array

//array_chunk($arr, $len, bool $preserve_keys) 切割陣列內元素成子陣列，preserve_keys = true會保留KEY
$d = [1,2,3,4];
print_r(array_chunk($d, 2));
output: [[1,2], [3,4]]

//implode(" ", $arr) Array to String connects with needles
$d = [1,2,3,4];
print_r(implode(" ", $d));
output: 1 2 3 4

//explode(" ", $str) String to Array split with needles
$s = "1 2 3 4";
print_r(explode(" ",$s));
output: [1,2,3,4]