Question

这个问题非常基础，我在stackoverflow中发现了许多类似的问题，但没有一个能适合我。

我设计了一个显示如下数据的表：

ID  name    Delete
1   abc     Delete
2   def     Delete

用于上述显示的代码是

<?php
$con=mysqli_connect("abc","abc","abc","abc");
// Check connection
if (mysqli_connect_errno()) 
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
$result = mysqli_query($con,"SELECT * FROM student");
echo "<table class='table table-striped table-bordered table-hover'>
<thead>
<tr>
<th>ID</th>
<th>name</th>
<th>delete</th>   
</tr>
</thead>";
while($row = mysqli_fetch_array($result)) 
{
echo "<tbody data-link='row' class='rowlink'>";
echo "<tr>";
echo "<td>" . $row['id'] . "</td>";
echo "<td>" . $row['name'] . "</td>";
echo "<td><a href='delete.php'>Delete</a></td>";
echo "</tr>";
echo "</tbody>";    
}
echo "</table>";
mysqli_close($con);
?>

delete.php的代码

<?php
$con=mysqli_connect("abc","abc","abc","abc");
// Check connection
if (mysqli_connect_errno()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
mysqli_query($con,"DELETE FROM student WHERE id='$id'");
mysqli_close($con);
header("Location: index.php");
?>

数据库视图

Id  name
1   abc
2   cdf

问题是它没有删除数据，也没有显示任何错误

我是这个领域的新手，如果有人能帮助我，我将不胜感激。

Answer 1

更改此行：

echo "<td><a href='delete.php'>Delete</a></td>";

到

echo "<td><a href=\"delete.php?id=".$row['id']."\">Delete</a></td>";

然后对于 delete.php （并且最初在评论中说明，$id未定义）。

<?php
$con=mysqli_connect("abc","abc","abc","abc");
// Check connection
if (mysqli_connect_errno()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

$id = $_GET['id']; // $id is now defined

// or assuming your column is indeed an int
// $id = (int)$_GET['id'];

mysqli_query($con,"DELETE FROM student WHERE id='".$id."'");
mysqli_close($con);
header("Location: index.php");
?>

它会起作用。

然而，出于安全考虑，您应该考虑使用mysqli with prepared statements或PDO with prepared statements，更安全。我在下面列举了一个例子。

以下是准备好的陈述示例：

<?php 
$DB_HOST = "xxx";
$DB_NAME = "xxx";
$DB_USER = "xxx";
$DB_PASS = "xxx";

$con = new mysqli($DB_HOST, $DB_USER, $DB_PASS, $DB_NAME);
if($con->connect_errno > 0) {
  die('Connection failed [' . $con->connect_error . ']');
}

$id = (int)$_GET['id'];

$update = $con->prepare("DELETE FROM student WHERE id = ?");
$update->bind_param('i', $id);
$update->execute();
$update->close();

Answer 2

在您的链接中添加GET参数：

echo "<td><a href='delete.php?id='".$row['id']."'>Delete</a></td>";

然后在delete.php查询中抓住它：

$id = $_GET['id'];
mysqli_query($con,"DELETE FROM student WHERE id='".$id."'");

Answer 3

您可能不希望每次删除行时都刷新页面，您可以使用ajax请求更快地执行此操作。您可以从以下链接获取完整代码：delete individual row from databse using ajax

使用php删除表的特定行

3 个答案: