Call to undefined function mysqli_connect() issue [duplicate] - php

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Fatal error: Call to undefined function mysqli_connect() in... while connecting PHP 5.4.22 and MySQL 5.5 with Apache 2.4.7
(5 answers)
Closed 3 years ago.
I am writing a simple registration code. I want to save username and password in db.
While running the page of registration.php on localhost I got this error.
Fatal error: Uncaught Error: Call to undefined function mysqli_connect() in C:\Users\Ammad Hassan\www\db.php:4 Stack trace: #0 C:\Users\Ammad Hassan\www\registration.php(10): require() #1 {main} thrown in C:\Users\Ammad Hassan\www\db.php on line 4
db.php is shown below
<?php
// Enter your Host, username, password, database below.
$con = mysqli_connect("localhost","root","","register");
// Check connection
if (mysqli_connect_errno())
{
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
?>
Registration.php
<?php
require('db.php');
// If form submitted, insert values into the database.
if (isset($_REQUEST['username'])){
// removes backslashes
$username = stripslashes($_REQUEST['username']);
//escapes special characters in a string
$username = mysqli_real_escape_string($con,$username);
$password = stripslashes($_REQUEST['password']);
$password = mysqli_real_escape_string($con,$password);
$query = "INSERT into `users` (username, password)
VALUES ('$username', '".md5($password)."')";
$result = mysqli_query($con,$query);
if($result){
echo "<div class='form'>
<h3>You are registered successfully.</h3>
<br/>Click here to <a href='login.php'>Login</a></div>";
}
}else{
?>
I want to run this page so that I can enter in the form.

Answer 1

Check if mysqli library is enabled in your php.ini.
Also consider using PDO instead, it is better and not tied to MySQL.