PHP 7.2 - 警告：count()：参数必须是实现 Countable 的数组或对象
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PHP 7.2 - Warning: count(): Parameter must be an array or an object that implements Countable
提问by Marwan Khaled
I just upgraded my PHP Versionfrom 5.6to 7.2. I used count()function in my login page, example:
我刚刚将我的PHP 版本从5.6升级到7.2。我count()在登录页面中使用了函数，例如：
if(!empty($_POST['username']) && !empty($_POST['password'])):
$records = $conn->prepare('SELECT id,username,password FROM users WHERE username = :username');
$records->bindParam(':username', $_POST['username']);
$records->execute();
$results = $records->fetch(PDO::FETCH_ASSOC);
$message = '';
if(count($results) > 0 && password_verify($_POST['password'], $results['password']) ){
$_SESSION['user_id'] = $results['id'];
header("Location: /");
} else {
$message = 'Sorry, those credentials do not match';
}
endif;
After searching, I found questions and answers similar to this one but they were related to WordPress that they modified some files, but I couldn't find a solution for it using Pure PHP.
搜索后，我发现了与此类似的问题和答案，但它们与 WordPress 相关，他们修改了一些文件，但我无法使用Pure PHP找到解决方案。
回答by Olim Saidov
PDO fetchreturns false on failure. So you need to check this case too:
PDOfetch在失败时返回 false。所以你也需要检查这个案例：
if($results && count($results) > 0 && password_verify($_POST['password'], $results['password']) ){
$_SESSION['user_id'] = $results['id'];
header("Location: /");
} else {
$message = 'Sorry, those credentials do not match';
}
