How to delete records from database using checkbox and button which are not in the form

Question

I have code like this in product.php: EDIT:

class Product {
private $conn;
private $id;
private $name;
private $description;
private $price;
private $category_id;
private $category_name;
private $created;


public function __construct($db) {
    $this->conn = $db;
}

public function readAll()
{
    $stmt = $this->conn->prepare('SELECT id, name, description, price, CategoryID, created FROM products');
    $stmt->execute();
    echo "<table class=\"highlight responsive-table\">
        <thead>
            <tr>
                <th data-field=\"empty\"> </th>
                <th data-field=\"name\">Name</th>
                <th data-field=\"description\">Description</th>
                <th data-field=\"price\">Price</th>
                <th data-field=\"category\">Category</th>
                <th data-field=\"action\">Action</th>
            </tr>
        </thead>";

    while ($result = $stmt->fetch(PDO::FETCH_ASSOC)) {
        $id = $result['id'];
        $n = $result['name'];
        $d = $result['description'];
        $p = $result['price'];
        $ca = $result['CategoryID'];
        $c = $result['created'];

        echo "<tbody>
             <tr>
             <td style=\"width:10%;\">

                        <input type=\"checkbox\" id=\"checkbox_".$id."\" name=\"checkbox[]\" />
                        <label for=\"checkbox_".$id."\"></label>

                </td>



                <td style=\"width:15%;\">" .$n. "</td>
                <td style=\"width:30%;\">" . $d. "</td>
                <td style=\"width:10%;\">" ."$".$p. "</td>
                <td style=\"width:15%;\">" . $ca. "</td>
                <td style=\"width:20%;\"> 
                    <a class=\"waves-effect waves-light btn\"><i class=\"material-icons\">mode_edit</i></a>
                    <a class=\"waves-effect waves-light btn\"><i class=\"material-icons\">delete</i></a>
                </td>";
    }

    echo "</tbody> </table>";


}

public function deleteSelected($ids) {
    $query = 'DELETE FROM products WHERE id=?';

    $stmt = $this->conn->prepare($query);

    if (is_array($ids)) {
        foreach ($ids as $id)
            $stmt->execute([$id]);
    }
    else {
        $stmt->execute([$ids]);
    }
}
}
/* ****** */
if($_SERVER['REQUEST_METHOD'] == 'POST'){
if (isset($_POST['delete']) && !empty($_POST['checkbox'])) {
     $checkboxArr = $_POST['checkbox'];
     foreach ($checkboxArr as $row) {
         $checkIds = explode("_", $row);
         $id = $checkIds[1];
         $cat = new Product($conn);

         //$id = filter_input ( INPUT_POST , 'id', FILTER_SANITIZE_NUMBER_INT );

         $cat->deleteSelected($id);
     }
 }
 }

and the button:

<button class="btn-floating btn-large waves-effect waves-light red" type="submit" value="Delete" name="delete">
                <a><i class="material-icons">clear</i></a>
            </button>

I'm displaying content of database in a table in index.php using readAll function. In 1st column I have checkbox. On the page are also few buttons, one of them is supposed to delete selected records from the database. I can do that using form like this:

<form action="" method="post">
<input type="text" name="id" id="id" placeholder="Please Enter Id"/><br /><br />
<input type="submit" value="Delete" name="delete" id="delete"/><br />

but how can I delete the record, without writing it's id in any form, just by using checkbox (in product.php) and button (in index.php) which is not in the form?

Answer 1

Using ajax , you can send a set of ID's to delete to a server code. Bind to the delete buttons onClick event using javascript ( ie. Pure, jQuery)

Or you can also trigger a form submission and set the id's to a hidden input. And do it in a non-ajax fashion.

Answer 2

Use name="checkbox[]" and id = "checkbox_".$id." .

Using checkbox[] you will get multiple selected checkbox with its id in comma separated.

class Product {
private $conn;
private $id;
private $name;
private $description;
private $price;
private $category_id;
private $category_name;
private $created;


public function __construct($db) {
    $this->conn = $db;
}

public function readAll()
{
    $stmt = $this->conn->prepare('SELECT id, name, description, price, CategoryID, created FROM products');
    $stmt->execute();
    echo " <form action="./objects/product.php" method="post">
 <table class=\"highlight responsive-table\">
        <thead>
            <tr>
                <th data-field=\"empty\"> </th>
                <th data-field=\"name\">Name</th>
                <th data-field=\"description\">Description</th>
                <th data-field=\"price\">Price</th>
                <th data-field=\"category\">Category</th>
                <th data-field=\"action\">Action</th>
            </tr>
        </thead>";

    while ($result = $stmt->fetch(PDO::FETCH_ASSOC)) {
        $id = $result['id'];
        $n = $result['name'];
        $d = $result['description'];
        $p = $result['price'];
        $ca = $result['CategoryID'];
        $c = $result['created'];

        echo "<tbody>
             <tr>
             <td style=\"width:10%;\">

                        <input type=\"checkbox\" id=\"checkbox_".$id."\" name=\"checkbox[]\" />
                        <label for=\"checkbox".$id."\"></label>

                </td>



                <td style=\"width:15%;\">" .$n. "</td>
                <td style=\"width:30%;\">" . $d. "</td>
                <td style=\"width:10%;\">" ."$".$p. "</td>
                <td style=\"width:15%;\">" . $ca. "</td>
                <td style=\"width:20%;\"> 
                    <a class=\"waves-effect waves-light btn\"><i class=\"material-icons\">mode_edit</i></a>
                    <a class=\"waves-effect waves-light btn\"><i class=\"material-icons\">delete</i></a>
                </td>";
    }
    echo " <input type="submit" value="Delete" name="delete" id="delete"/></form>";
    echo "</tbody> </table>";


}

public function deleteSelected($ids) { 
    $query = 'DELETE FROM products WHERE id=?';

    $stmt = $this->conn->prepare($query);

    if (is_array($ids)) {
        foreach ($ids as $id)
            $stmt->execute([$id]);
    }
    else {
        $stmt->execute([$ids]);
    }
}

/* ****** */

In below code we are getting comma separated selected checkbox array and delete it using foreach loop of $_POST['checkbox'] array.

if($_SERVER['REQUEST_METHOD'] == 'POST'){
    if ( isset( $_POST['delete']) && !empty( $_POST['checkbox']) ) {
        $checkboxArr = $_POST['checkbox'];
        foreach($checkboxArr as $id)
        {
            $cat = new Product($conn);
            //$id = filter_input ( INPUT_POST , 'id', FILTER_SANITIZE_NUMBER_INT );
            $cat->deleteSelected($id);
        }
    }
}