Question

以下代码将显示＆＃34;已找到电子邮件＆＃34;如果数据库中存在电子邮件地址，但如果数据库中不存在数据，则不显示任何内容。

我无法显示＆＃34;找不到电子邮件＆＃34;如果它不存在。

你能看出出了什么问题吗？

<?php
if (isset($_POST['submit'])) {
    error_reporting(E_ALL);
    $email = $_POST['email'];
    include($_SERVER["DOCUMENT_ROOT"]."/dbconnect.php");
    $sql    = "SELECT * FROM membership_main WHERE email = '$email' ";
    $result = mysqli_query($conn, $sql);

    while($rows = mysqli_fetch_assoc($result)){
        if(mysqli_num_rows($result) == 0) {
            echo "email was not found";
        } else {
            echo "email was found";
        }
    }

    mysqli_close($conn);
}
?>

Answer 1

你可以尝试这段代码......

<?php

if (isset($_POST['submit'])) {

    error_reporting(E_ALL);

    $email = $_POST['email'];

    include($_SERVER["DOCUMENT_ROOT"] . "/dbconnect.php");

    $sql = "SELECT * FROM membership_main WHERE email = '$email' ";

    $result = mysqli_query($conn, $sql);

    if (mysqli_num_rows($result) > 0) {
        echo "email was found";
    } else {
        echo "email was not found";
    }


    mysqli_close($conn);
}
?>

Answer 2

你应该将代码移到

之外

while($rows=mysqli_fetch_assoc($result)){
if(mysqli_num_rows($result)==0) {
echo "email was not found";
} else {
echo "email was found";
}
}

到

if(mysqli_num_rows($result)==0) {
echo "email was not found";
} else {
echo "email was found";
}

Answer 3

删除while循环，然后查看mysqli_num_rows()。

数据存在后使用while循环。

<?php

if (isset($_POST['submit'])) {

error_reporting(E_ALL);

$email = $_POST['email'];

include($_SERVER["DOCUMENT_ROOT"]."/dbconnect.php");

$sql  = "SELECT * FROM membership_main WHERE email = '$email' ";

$result = mysqli_query($conn, $sql);

if(mysqli_num_rows($result) == 0) {
echo "email was not found";
} else {
 while($row = mysqli_fetch_assoc($result))
 {
    echo $row['email']." email was found";
 }
}

mysqli_close($conn);

}

?>

如果找到数据，则显示文本

3 个答案: