如何使用mysqli_fetch_array从MySQL列获取数组

Question

我正在尝试撰写IP禁令。 用户IP存储在数据库中。 我可以将该用户IP手动添加到黑名单中。 不幸的是，以下代码不起作用。 我认为问题在于将阵列移出数据库。

$ip = $_SERVER['REMOTE_ADDR'];
$bannedips = array();
$notBanned = true; //later used to check, if ip is banned

$sql = "SELECT ip FROM ipban";
$result = mysqli_query($conn, $result);
while($row = mysql_fetch_array($result, MYSQL_NUM)){
    $bannedips[] = $row;
}
if (in_array($ip, $bannedips)) {
    $notBanned = false;
}

Answer 1

而不是查询所有条目，您应该只搜索ip以获得性能原因

$ip = $_SERVER['REMOTE_ADDR'];
$notBanned = true; //later used to check, if ip is banned

$sql = "SELECT ip FROM ipban WHERE ip = ?";
if ($stmt = mysqli_prepare($conn, $sql)) {
    /* bind parameters for markers */
    mysqli_stmt_bind_param($stmt, "s", $ip);

    if($result = mysqli_query($conn, $sql)){
        $notBanned = false;
        mysqli_free_result($result);
    }
}

面向对象的样式应为：

$mysqli = new mysqli(/* Whatever needed to establish connection */);
$ip = $_SERVER['REMOTE_ADDR'];
$notBanned = true; //later used to check, if ip is banned

$sql = "SELECT ip FROM ipban WHERE ip = ?";

if ($stmt = $mysqli->prepare($sql)){
    $stmt->bind_param("s", $ip);
    $stmt->execute();
    if($stmt && $stmt->num_rows > 0){
        $notBanned = false;
    }
}

Answer 2

只是改变：

while($row = mysql_fetch_array($result, MYSQL_NUM)){
    $bannedips[] = $row;

而且您无法将mysqli函数与mysql合并

$result = mysqli_query($conn, $result);
while($row = mysql_fetch_array($result, MYSQL_NUM)){

最后（编辑）：

$host = "example";
$username = "example";
$password = "example";
$database = "example";

$ip = $_SERVER['REMOTE_ADDR'];
$bannedips = array();
$notBanned = true; //later used to check, if ip is banned

$connection = new mysqli($host, $username, $password, $database);

$query = $connection->query("SELECT ip FROM ipban");

while ($row = $query->fetch_array()) {
    $bannedips[] = $row['ip'];
}

if (in_array($ip, $bannedips)) {
    $notBanned = false;
}  

您可以在以下位置阅读更多信息：

http://php.net/manual/zh/function.mysql-fetch-array.php

Answer 3

该问题保存在您的while循环内。 在将数据追加到$ bannedips数组的同时，您忘记了从$ row数组中选择第零个（ip列）键。

将$ row更改为row [0]，如下所示：

while($row = mysql_fetch_array($result, MYSQL_NUM)){
    $bannedips[] = $row[0];
}