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How to Delete Multiple Rows Using Checkboxes in PHP: Addressing Common Errors and Ensuring Successful Execution?
How to Delete Multiple Rows Using Checkboxes in PHP: Addressing Common Errors and Ensuring Successful Execution?
Oct 26, 2024 am 04:00 AM
Delete Multiple Rows by Selecting Checkboxes Using PHP: Troubleshooting Common Errors
When deleting multiple rows from a MySQL database table using PHP, selecting links using checkboxes requires careful coding to ensure successful execution. This code snippet offers a solution to a common issue:
<code class="php"><html>
<head>
<title>Links Page</title>
</head>
<body>
<h2>Choose and delete selected links.</h2>
<?php
$dbc = mysqli_connect('localhost','root','admin','sample') or die('Error connecting to MySQL server');
$query = "select * from links ORDER BY link_id";
$result = mysqli_query($dbc,$query) or die('Error querying database');
$count=mysqli_num_rows($result);
?>
<table width="400" border="0" cellspacing="1" cellpadding="0">
<tr>
<td>
<form name="form1" method="post" action="">
<table width="400" border="0" cellpadding="3" cellspacing="1" bgcolor="#CCCCCC">
<tr>
<td bgcolor="#FFFFFF"> </td>
<td colspan="3" bgcolor="#FFFFFF">
<strong>Delete multiple links</strong>
</td>
</tr>
<tr>
<td align="center" bgcolor="#FFFFFF">#</td>
<td align="center" bgcolor="#FFFFFF">
<strong>Link ID</strong>
</td>
<td align="center" bgcolor="#FFFFFF">
<strong>Link Name</strong>
</td>
<td align="center" bgcolor="#FFFFFF">
<strong>Link URL</strong>
</td>
</tr>
<?php
while ($row=mysqli_fetch_array($result)) {
?>
<tr>
<td align="center" bgcolor="#FFFFFF">
<input name="checkbox[]" type="checkbox" value="<?php echo $row['link_id']; ?>">
</td>
<td bgcolor="#FFFFFF"> <?php echo $row['link_id']; ?> </td>
<td bgcolor="#FFFFFF"> <?php echo $row['link_name']; ?> </td>
<td bgcolor="#FFFFFF"> <?php echo $row['link_url']; ?> </td>
</tr>
<?php
}
?>
<tr>
<td colspan="4" align="center" bgcolor="#FFFFFF">
<input name="delete" type="submit" value="Delete">
</td>
</tr>
</table>
</form>
</td>
</tr>
</table>
<?php
// Check if delete button active, start this
if(isset($_POST['delete']))
{
$checkbox = $_POST['checkbox'];
for($i=0; $i<count($checkbox); $i++) {
$del_id = $checkbox[$i];
$sql = "DELETE FROM links WHERE link_id='$del_id'";
$result = mysqli_query($dbc, $sql); // Pass the database connection here
}
// if successful redirect to view_links.php
if($result){
echo '<meta http-equiv="refresh" content="0;URL=view_links.php">';
}
}
mysqli_close($dbc);
?>
</body>
</html></code>
The fix:
- Treat the checkbox name as an array: name="checkbox[]" instead of name="checkbox".
- Pass the $dbc database connection to each mysqli_query call, as shown in $result = mysqli_query($dbc, $sql);.
With these modifications, the code should correctly delete multiple rows based on the selected checkboxes.
The above is the detailed content of How to Delete Multiple Rows Using Checkboxes in PHP: Addressing Common Errors and Ensuring Successful Execution?. For more information, please follow other related articles on the PHP Chinese website!
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