php - mysqli to pdo - php

Question

Hello everyone I'm completely new to mysqli and PDO. I tried to convert my msqli code to PDO but I keep getting errors. Can someone please help me? the error is like when i click on post, nothing happens and I searched everywhere how to convert from msqli to pdo and I converted some of them but it still doesn't work
<?php
$databaseHost = 'localhost';
$databaseName = 'test';
$databaseUsername = 'test';
$databasePassword = 'pass';
try {
$dbConn = new PDO("mysql:host={$databaseHost};dbname={$databaseName}", $databaseUsername, $databasePassword);
$dbConn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
} catch(PDOException $e) {
echo $e->getMessage();
}
if (isset($_POST['save'])) {
$name = $_POST['name'];
$comment = $_POST['comment'];
$sql = "INSERT INTO comments (name, comment) VALUES ('{$name}', '{$comment}')";
if ($result = $dbConn->query($sql)) {
$id = $link->insert_id;
$saved_comment = '<div class="comment_box">
<span class="delete" data-id="' . $id . '" >delete</span>
<span class="edit" data-id="' . $id . '">edit</span>
<div class="display_name">'. $name .'</div>
<div class="comment_text">'. $comment .'</div>
</div>';
echo $saved_comment;
}else {
echo "Error: ".($dbConn);
}
exit();
}
// delete comment fromd database
if (isset($_GET['delete'])) {
$id = $_GET['id'];
$sql = "DELETE FROM comments WHERE id=" . $id;
($dbConn->prepare($sql));
exit();
}
if (isset($_POST['update'])) {
$id = $_POST['id'];
$name = $_POST['name'];
$comment = $_POST['comment'];
$sql = "UPDATE comments SET name='{$name}', comment='{$comment}' WHERE id=".$id;
if ($dbConn->prepare($sql)) {
$id =($dbConn);
$saved_comment = '<div class="comment_box">
<span class="delete" data-id="' . $id . '" >delete</span>
<span class="edit" data-id="' . $id . '">edit</span>
<div class="display_name">'. $name .'</div>
<div class="comment_text">'. $comment .'</div>
</div>';
echo $saved_comment;
}else {
echo "Error: ". ($dbConn);
}
exit();
}
// Retrieve comments from database
$sql = "SELECT * FROM comments";
$result = $dbConn->prepare($sql);
$comments = '<div id="display_area">';
while($row = $result->fetch(PDO::FETCH_ASSOC)) {
$comments .= '<div class="comment_box">
<span class="delete" data-id="' . $row['id'] . '" >delete</span>
<span class="edit" data-id="' . $row['id'] . '">edit</span>
<div class="display_name">'. $row['name'] .'</div>
<div class="comment_text">'. $row['comment'] .'</div>
</div>';
}
$comments .= '</div>';
?>

Answer 1

You used ->prepare(), but did not use ->execute().
Documentation:
http://php.net/manual/en/pdostatement.execute.php