PHP检查日期时间格式使用preg_match和checkdate错误的结果

Question

我想使用preg_match()和checkdate()函数验证日期时间格式。我的格式是"dd/MM/yyyy hh: MM:ss"。我的代码有什么问题?

function checkDatetime($dateTime){
    $matches = array();
    if(preg_match("/^(d{2})-(d{2})-(d{4}) ([01][0-9]|2[0-3]):([0-5][0-9]):([0-5][0-9])$/", $dateTime, $matches)){
        print_r($matches); echo "<br>";
        $dd = trim($matches[1]);
        $mm = trim($matches[2]);
        $yy = trim($matches[3]);
        return checkdate($mm, $dd, $yy); // <- Problem here?
    }else{
        echo "wrong format<br>";
        return false;
    }    
} 
//wrong result
if(checkDatetime("12-21-2000 03:04:00")){
    echo "checkDatetime true<br>";
}else{
    echo "checkDatetime false<br>";
}
//correct result
if(checkdate("12", "21", "2000")){
    echo "checkdate true<br>";
}else{
    echo "checkdate false<br>";
}

输出:

Array ( [0] => 12-21-2000 03:04:00 [1] => 12 [2] => 21 [3] => 2000 [4] => 03 [5] => 04 [6] => 00 )
checkDatetime false
checkdate true

Answer 1

if(checkDatetime("12-21-2000 03:04:00"))导致

$dd = 12
$mm = 21
$yy = 2000

然后调用return checkdate($mm, $dd, $yy);，相当于return checkdate(21, 12, 2000);

很明显，$mm不能是21，但我不能说如果你传递错误的格式checkDatetime，或者如果你在正则表达式中解析它是错误的。