PHP Mysql 删除查询无法正常工作

Question

我正在从 MYSQL 数据库中提取产品列表，并对每个产品使用删除按钮，以防操作员想要删除该产品。

问题是，每次我点击列表中任何产品上的删除按钮时，第一个元素都会被删除。

我下面的代码有什么问题？

Products页：

<?php
$link=mysqli_connect("localhost","root","","smartcart");
$prod="select * from products";
$rw=mysqli_query($link,$prod) or die(mysqli_errno()."in query $prod");
$count=1;

while($row=mysqli_fetch_assoc($rw))
{
    echo "<tr>";
    echo "<td>".$count."</td>";
    echo "<td>".$row['prod_id']."</td>";
    echo "<td>".$row['prod_name']."</td>";
    echo "<td>".$row['prod_price']."</td>";
    echo "<td><form action='delete_prod.php' id='delete' method='get'>";
    echo "<input type='hidden' name='prod_id' value='".$row['prod_id']."' />";
    echo "<button type='submit' form = 'delete' class='btn btn-default' name='delete'>Delete</button>";
    echo "</form></td>";
    $count=$count+1;                        
}

mysqli_free_result($rw);
?>

delete_prod.php:

<?php
if(isset($_GET['delete']))
{
    include "connection.php";
    $prod_id=$_REQUEST['prod_id'];
        $del="delete from products where prod_id=$prod_id";
    if (mysqli_query($link,$del))
    {
        echo "Successfully deleted";
        unset($_POST['delete']);
    }
    else
    {
        echo "Delete operation Failed";
    }
    header('location:show_db.php');
}
?>

我认为我严重遗漏了一些简单的观点，但我无法明白它是什么。

Answer 1

很可能是因为您设置了id="delete". 通常 id 属性值不会重复。

echo "<td><form action='delete_prod.php' id='delete' method='get'>";
echo "<button type='submit' form = 'delete' class='btn btn-default' name='delete'>Delete</button>";

提交按钮获取第一个 ID，从而获取第一个隐藏输入。

或者，您可以像这样设计按钮并用作标记：

无需打印每份表格！只需将其与表格包裹起来即可：

echo "<form action='delete_prod.php' id='delete' method='get'>";

echo '<table>';
while($row = mysqli_fetch_assoc($result)) {
    $prod_id = $row['prod_id'];
    echo "<tr>";
        echo "<td>".$count."</td>";
        echo "<td>".$row['prod_id']."</td>";
        echo "<td>".$row['prod_name']."</td>";
        echo "<td>".$row['prod_price']."</td>";
        echo "<td>";
        // each id is assigned to each button, so that when its submitted you get the designated id, the one that you clicked
        echo "<button type='submit' value='$prod_id' class='btn btn-default' name='delete'>Delete</button>";
        echo "</td>";
    echo '</tr>';
}

echo '</table>';
echo '</form>';

然后在PHP中处理：

if(isset($_GET['delete'])) // as usual
{
    include "connection.php";
    $prod_id = $_GET['delete']; // get the id
    // USE PREPARED STATEMENTS!!!
    $del="DELETE FROM products WHERE prod_id = ?";
    $delete = $link->prepare($del);
    $delete->bind_param('i', $prod_id);
    $delete->execute();
    // don't echo anything else, because you're going to use header
    if($delete->affected_rows > 0) {
        header('location:show_db.php');
    } else {
        echo 'Sorry delete did not push thru!';
    }
}