通过复选框删除数据库条目

I have been trying to delete certain rows from the database using a few checkboxes. So far I've managed to echo out the content of the MySQL table but deleting rows through the checkboxes doesn't seem to work.

<table class="ts">
        <tr>
            <th class="tg-031e" style='width:1px'>ID</th> 
            <th class="tg-031e">IP address</th>
            <th class="tg-031e">Date added</th>
            <th class="tg-031e">Reason</th>
        </tr>

        <?php include 'connect.php';

            $SQL = "SELECT `ID`, `IPaddress`, `DateAdded`, `Reason` FROM `banned`";
            $exec = mysql_query($SQL, $connection);

            while ($row = mysql_fetch_array($exec)){
                    echo "<tr class='tg-031h'>";
                    echo "<td class='tg-031e'><form method='post'><input type='checkbox' name='checkbox' value=" . $row['ID'] . "></form></td>";
                    echo "<td class='tg-031e'>" . $row['IPaddress'] . "</td>";
                    echo "<td class='tg-031e'>" . $row['DateAdded'] . "</td>";
                    echo "<td class='tg-031e'>" . $row['Reason'] . "</td>";
                    echo "</tr>"; 
            }

            echo "</table><form method='post'><input name='delete' type='submit' value='Delete'></form>";

            if (isset($_POST['delete']) && isset($_POST['checkbox'])) {
                foreach($_POST['checkbox'] as $id){
                    $id = (int)$id;
                    $delete = "DELETE FROM banned WHERE ID = $id"; 
                    mysql_query($delete);
                }
            }

            ?>

I don't get any result as the check does not pass but I don't know what's wrong with it. The query is correct though, so the issue must be with selecting the checkboxes and getting their ID.

Here, it's tested and working while using mysqli_ instead of mysql_

Replace with your own credentials.

A few things, your checkbox did need square brackets around the named element as I mentioned in my comment(s), i.e. name='checkbox[]' otherwise you would receive an invalid foreach argument error.

Sidenote: There stands to do a bit of formatting, but it works.

<table class="ts">
        <tr>
            <th class="tg-031e" style='width:1px'>ID</th> 
            <th class="tg-031e">IP address</th>
            <th class="tg-031e">Date added</th>
            <th class="tg-031e">Reason</th>
        </tr>

<?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 . ']');
}

$SQL = "SELECT `ID`, `IPaddress`, `DateAdded`, `Reason` FROM `banned`";
$exec = mysqli_query($con,$SQL);

echo "<form method='post'>";

        while ($row = mysqli_fetch_array($exec)){
                echo "<tr class='tg-031h'>";
                echo "<td class='tg-031e'><input type='checkbox' name='checkbox[]' value='" . $row[ID] . "'></td>";

                echo "<td class='tg-031e'>" . $row['IPaddress'] . "</td>";
                echo "<td class='tg-031e'>" . $row['DateAdded'] . "</td>";
                echo "<td class='tg-031e'>" . $row['Reason'] . "</td>";
        }

echo "</tr></table>"; 

        echo "<input name='delete' type='submit' value='Delete'></form>";

        if (isset($_POST['delete']) && isset($_POST['checkbox'])) {
            foreach($_POST['checkbox'] as $id){
                $id = (int)$id;

                $delete = "DELETE FROM banned WHERE ID = $id"; 
                mysqli_query($con,$delete);
            }
        }

?>

Do use mysqli_* with prepared statements, or PDO with prepared statements for this.

Edit: mysql_ version

<table class="ts">
        <tr>
            <th class="tg-031e" style='width:1px'>ID</th> 
            <th class="tg-031e">IP address</th>
            <th class="tg-031e">Date added</th>
            <th class="tg-031e">Reason</th>
        </tr>

<?php

include 'connect.php';

$SQL = "SELECT `ID`, `IPaddress`, `DateAdded`, `Reason` FROM `banned`";
$exec = mysql_query($SQL, $connection);

echo "<form method='post'>";

        while ($row = mysql_fetch_array($exec)){
                echo "<tr class='tg-031h'>";
                echo "<td class='tg-031e'><input type='checkbox' name='checkbox[]' value='" . $row[ID] . "'></td>";

                echo "<td class='tg-031e'>" . $row['IPaddress'] . "</td>";
                echo "<td class='tg-031e'>" . $row['DateAdded'] . "</td>";
                echo "<td class='tg-031e'>" . $row['Reason'] . "</td>";
        }

echo "</tr></table>"; 

        echo "<input name='delete' type='submit' value='Delete'></form>";

        if (isset($_POST['delete']) && isset($_POST['checkbox'])) {
            foreach($_POST['checkbox'] as $id){
                $id = (int)$id;

                $delete = "DELETE FROM banned WHERE ID = $id"; 
                mysql_query($delete);
            }
        }

?>

You should do something similar to this (semi pseudo):

<form method="post">

    /begin loop/

    echo '<input type="checkbox" name="row[' . $row['ID'] . ']" />';

    /end loop/

    <input type="submit" />

</form>

Then try to put this on the processor page, on top of it:

if ( !empty( $_POST ) )
{
    echo '<pre>' . print_r( $_POST, true ) . '</pre>';
    die( 'see? :-)' );
}

. . . .

Okay here's your code, edited:

<?php if ( !empty( $_POST ) ) { echo '<pre>'.print_r( $_POST, true ).'</pre>'; die( 'See?' ); ?>
<form method="post">
<table class="ts">
    <tr>
        <th class="tg-031e" style='width:1px'>ID</th> 
        <th class="tg-031e">IP address</th>
        <th class="tg-031e">Date added</th>
        <th class="tg-031e">Reason</th>
    </tr>

    <?php include 'connect.php';

        $SQL = "SELECT `ID`, `IPaddress`, `DateAdded`, `Reason` FROM `banned`";
        $exec = mysql_query($SQL, $connection);

        while ($row = mysql_fetch_array($exec)){
                echo "<tr class='tg-031h'>";
                echo "<td class='tg-031e'><input type='checkbox' name='row[$row['ID']]'></td>";
                echo "<td class='tg-031e'>" . $row['IPaddress'] . "</td>";
                echo "<td class='tg-031e'>" . $row['DateAdded'] . "</td>";
                echo "<td class='tg-031e'>" . $row['Reason'] . "</td>";
                echo "</tr>"; 
        }

        echo "</table><input name='delete' type='submit' value='Delete'>";

        if (isset($_POST['delete']) && isset($_POST['checkbox'])) {
            foreach($_POST['checkbox'] as $id){
                $id = (int)$id;
                $delete = "DELETE FROM banned WHERE ID = $id"; 
                mysql_query($delete);
            }
        }

        ?>

</form>

The Deletion query hasn't been fixed yet. Try to fix it yourself :-)