来自 mysqli_Query 的回显结果

Question

我正在制作一个供自己使用的个人脚本，我需要知道如何回显 mysqli_query 的结果。我的代码如下：

$conn = mysqli_connect($servername, $username, $password, $dbname);

if(isset($_POST['commercial'])){
if (isset($_POST['0'])){
    $sql = "SELECT email FROM CommercialEmails WHERE articleid = '$_POST[article]' AND dripid = 1 AND sent='a'";
    $resultsd1 = mysqli_query($conn, $sql);
    echo $resultsd1;
}   
if (isset ($_POST['1'])){
    $sql = "SELECT email FROM CommercialEmails WHERE articleid = '$_POST[article]' AND dripid = 2 AND sent='a'";
    $resultsd2 = mysqli_query($conn, $sql);
    echo $resultsd2;
}   
if (isset($_POST['2'])){
    $sql = "SELECT email FROM CommercialEmails WHERE articleid = '$_POST[article]' AND dripid = 3 AND sent='a'";
    $resultsd3 = mysqli_query($conn, $sql);
    echo $resultsd3;
}
if (isset ($_POST['3'])){
    $sql = "SELECT email FROM CommercialEmails WHERE articleid = '$_POST[article]' AND dripid = 4 AND sent='a'";
    $resultsd4 = mysqli_query($conn, $sql);
    echo $resultsd4;
}
if (isset ($_POST['4'])){
    $sql = "SELECT email FROM CommercialEmails WHERE articleid = '$_POST[article]' AND dripid = 5 AND sent='a'";
    $resultsd5 = mysqli_query($conn, $sql);
    echo $resultsd5;
}

}
?>

Answer 1

如果要输出多行

if (isset($_POST['0'])) {
 $sql = "SELECT email FROM CommercialEmails WHERE articleid = '$_POST[article]' AND dripid = 1 AND sent='a'";
 $resultsd1 = mysqli_query($conn, $sql);

 while ($row = mysqli_fetch_assoc($resultsd1))
 {
    echo $row['email'];
 }
}

如果只有1行

if (isset($_POST['0'])){
 $sql = "SELECT email FROM CommercialEmails WHERE articleid = '$_POST[article]' AND dripid = 1 AND sent='a' LIMIT 1";
 $resultsd1 = mysqli_query($conn, $sql);

 $row = mysqli_fetch_assoc($resultsd1);

 echo $row['email'];
}

Answer 2

首先正如@fred-ii所说，转义你的post，你的$_POST访问也有错误，你缺少文章关键字周围的引号，最后使用mysqli_fetch_assoc访问您的结果：

...
if (isset($_POST['0'])) {
    $article = mysqli_real_escape_string($conn, $_POST['article']);
    $sql = "SELECT email FROM CommercialEmails WHERE articleid = '$article' AND dripid = 1 AND sent='a'";
    if ($resultsd1 = mysqli_query($conn, $sql)) {
        if ($row = mysqli_fetch_assoc($resultsd1)) {
            echo $row['email'];
        }
    }
}
...

Answer 3

您可以简单地使用 foreach 循环在结果对象上循环。如果要将所有行提取到 PHP 变量中，可以使用 fetch_all().

$result = mysqli_query($conn, 'SELECT ...');
foreach($result as $row) {
    print_r($row);
    // do something with each row
}
// or
$result = $conn->('SELECT ...')->fetch_all(MYSQLI_ASSOC);
foreach($result as $row) {
    print_r($row);
    // do something with each row
}

但是，在您的情况下，您根本不应该使用 mysqli_query()！这使您容易受到 SQL 注入攻击。您必须使用参数绑定，它可用于准备好的语句。

例如，您的固定查询如下所示：

$stmt = $con->prepare("SELECT email FROM CommercialEmails WHERE articleid = ? AND dripid = 1 AND sent = 'a' ");
$stmt->bind_param('s', $_POST['article']);
$stmt->execute();
$result = $stmt->get_result();
foreach ($result as $row) {
    print_r($row);
}

不同的是我的变量没有和SQL分开，所以没有注入的风险。你不应该允许直接在 SQL 查询中输入任何变量。正确地做到这一点并不难。

另外，你真的不需要那么多重复代码。您也可以参数化 dripid 并减少代码中的行数。

来自 mysqli_Query 的回显结果

Echo results from mysqli_Query

php

mysqli