update data in php with condition

Question

I make a registration page. So Registration page ready and fetch data with page view data. so update option not working some errors.... attach all file zip folder with database...   Error showing this    Notice : Undefined variable: conn in C:\xampp\htdocs\registration\update.php on line 25
Fatal error : Call to a member function query() on null in C:\xampp\htdocs\registration\update.php on line 25       Please resolve.......or new code comment.... Thanks so much....        if(!isset($_GET['id'])) { exit('User Not Exists.'); } $mysqli = new mysqli("localhost", "root", "", "test"); // Check connection if($mysqli === false){ die("ERROR: Could not connect. " . $mysqli->connect_error); } // Attempt select query execution $sql = "SELECT * FROM record where id = ".$_GET['id']; if($result = $mysqli->query($sql)){ if($result->num_rows > 0){ $row = $result->fetch_array(); } } if(isset($_POST['update'])) { $sql = "UPDATE record SET name='".$_POST['name']."', email='".$_POST['email']."', mobile='".$_POST['mobileno']."', address='".$_POST['address']."' WHERE id=".$_GET['id']; if ($conn->query($sql) === TRUE) { echo "Record updated successfully"; } else { echo "Error updating record: " . $conn->error; } } ?> Registration Name:- * " placeholder=" name" id=""/> Email * " id=""/> Address * " /> Mobile No * " />

Bharathi Raja · Accepted Answer

use $mysqli instead of $conn   or add this   $conn=mysqli_connect("localhost","root",""); mysqli_select_db($con,'db') or die(mysqli_error($con))