I've got some errors in my code [duplicate] - php

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mysqli_real_escape_string() expects exactly 2 parameters, 1 given
(5 answers)
Closed 1 year ago.
Warning: mysqli_real_escape_string() expects exactly 2 parameters, 1
given in C:\xampp\htdocs\login2\login.php on line 28
Warning: mysqli_real_escape_string() expects exactly 2 parameters, 1
given in C:\xampp\htdocs\login2\login.php on line 29
Warning: mysqli_select_db() expects parameter 1 to be mysqli, string
given in C:\xampp\htdocs\login2\login.php on line 31
Warning: mysqli_num_rows() expects parameter 1 to be mysqli_result,
string given in C:\xampp\htdocs\login2\login.php on line 35
Can anybody help me figure it out?
here is my code below.
<?php
session_start(); // Starting Session
$error=''; // Variable To Store Error Message
if (isset($_POST['submit'])) {
if (empty($_POST['username']) || empty($_POST['password'])) {
$error = "Username or Password is invalid";
}
else
{
// Define $username and $password
$username=$_POST['username'];
$password=$_POST['password'];
// Establishing Connection with Server by passing server_name, user_id and password as a parameter
$servername = "localhost";
$username = "root";
$password = "";
$dbname = "server1";
// Create connection
$conn = new mysqli($servername, $username, $password,$dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
// To protect mysqli injection for Security purpose
$username = stripslashes($username);
$password = stripslashes($password);
$username = mysqli_real_escape_string($username);
$password = mysqli_real_escape_string($password);
// Selecting Database
$db = mysqli_select_db("server1", $conn);
// SQL query to fetch information of registerd users and finds user match.
$query = "select * from account where password='$password' AND username='$username'";
$result = mysqli_query($conn, $query) or trigger_error("Query Failed! SQL: $query - Error: ". mysqli_error($mysqli), E_USER_ERROR);;
$rows = mysqli_num_rows($query);
if ($rows == 1) {
$_SESSION['login_user']=$username; // Initializing Session
header("location: profile.php"); // Redirecting To Other Page
} else {
$error = "Username or Password is invalid";
}
mysqli_close($conn); // Closing Connection
}
}
?>

Answer 1

You can use both procedural style or object oriented style. Since object oriented approach is more encouraged I'll show that.
...
$username = $conn->real_escape_string($username);
$password = $conn->real_escape_string($password);
...
$db = $conn->select_db("server1"); //redundant line
...
$result = $conn->query( $query)
$rows = $conn->num_rows($query);
...
$conn->close();
And all that was needed to solve this was checking the documentation properly http://php.net/docs.php

Answer 2

Please check Syntax of mysqli_real_escape_string
You need to mention the $con variable as well:
$username = mysqli_real_escape_string($con, $username);
$password = mysqli_real_escape_string($con, $password);
Also, you're already specifying your database in this line:
$conn = new mysqli($servername, $username, $password,$dbname);
So, this below line is redundant. You should just remove this:
$db = mysqli_select_db("server1", $conn);