从MySQL改为MySQLi，不再工作了

Question

While changing mysql to mysqli I went from a completely working php file, to one thats not! I followed the instructions for every change, could you help? Here is my code before(mysql) and after (mysqli):

Before(mysql):

<?php

function db_open() {
    $dtbhost=":/something/home/something2/mysql/run/mysql.sock";
    $dtbuser="root";
    $dtbpass="mypass";
    $dtbname="mydb";
    $connection   =   mysql_connect("$dtbhost",   "$dtbuser",   "$dtbpass") 
        or die('00: No Connection');
    @ mysql_select_db("$dtbname") or die('01: No Database');      
}

session_start(); // Starting Session
$error=''; // Variable To Store Error Message
if (isset($_POST['submit'])) {
    if (empty($_POST['username']) || empty($_POST['password'])) {
        echo ("<SCRIPT LANGUAGE='JavaScript'> 
            window.alert('You did not complete all of the required fields') 
            window.location.href='index.html' 
            </SCRIPT>");
    }
    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
    db_open(); 
    // To protect MySQL injection for Security purpose
    $username = stripslashes($username);
    $password = stripslashes($password);
    $username = mysql_real_escape_string($username);
    $password = mysql_real_escape_string($password);
    $query = mysql_query("SELECT * FROM login_users WHERE username = '$username' AND password = '$password'") 
            or die(mysql_error());

    $rows = mysql_num_rows($query);
    if ($rows == 1) {
        $_SESSION['login_user']=$username; // Initializing Session
        header("location: profile.html"); // Redirecting To Other Page

    } else {
        echo ("<SCRIPT LANGUAGE='JavaScript'> 
            window.alert('Wrong username password combination. Please re-enter.') 
            window.location.href='index.html' 
            </SCRIPT>");
    }
    mysql_close($connection); // Closing Connection
    }
}
?>

After(mysqli):

<?php

function db_open() {
    $dtbhost=":/something/home/something2/mysql/run/mysql.sock";
    $dtbuser="root";
    $dtbpass="mypass";
    $dtbname="mydb";
    $con = mysqli_connect("$dtbhost","$dtbuser","$dtbpass","$dtbname");

    // Check connection
    if (mysqli_connect_errno())
      {
        echo "Failed to connect to MySQL: " . mysqli_connect_error();
      }
}

session_start(); // Starting Session
$error=''; // Variable To Store Error Message
if (isset($_POST['submit'])) {
    if (empty($_POST['username']) || empty($_POST['password'])) {
        echo ("<SCRIPT LANGUAGE='JavaScript'> 
            window.alert('You did not complete all of the required fields') 
            window.location.href='index.html' 
            </SCRIPT>");
    }
    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
    db_open(); 
    // To protect MySQL injection for Security purpose
    $username = stripslashes($username);
    $password = stripslashes($password);
    $username = mysqli_real_escape_string($con, $username);
    $password = mysqli_real_escape_string($con, $password);

    $query = mysqli_query($con, "SELECT * FROM login_users WHERE username = '$username' AND password = '$password'") 
            or die(mysqli_error());

    $rows = mysqli_num_rows($query);
    if ($rows == 1) {
        $_SESSION['login_user']=$username; // Initializing Session
        header("location: profile.html"); // Redirecting To Other Page

    } else {
        echo ("<SCRIPT LANGUAGE='JavaScript'> 
            window.alert('Wrong username password combination. Please re-enter.') 
            window.location.href='index.html' 
            </SCRIPT>");
    }
    mysqli_close($con); // Closing Connection
    }
}
?>

The errors I get are:

Warning: mysqli_connect(): php_network_getaddresses: getaddrinfo failed: hostname nor servname provided, or not known in /something/home/something2/public_html/login.php on line 8

Warning: mysqli_connect(): (HY000/2002): php_network_getaddresses: getaddrinfo failed: hostname nor servname provided, or not known in /something/home/something2/public_html/login.php on line 8 Failed to connect to MySQL: php_network_getaddresses: getaddrinfo failed: hostname nor servname provided, or not known

( line 8 is: $con = mysqli_connect("$dtbhost","$dtbuser","$dtbpass","$dtbname"); )

Which then trigger more errors because $con is empty. Any help would be appreciated, thanks!

Answer 1

$dtbhost variable should be an IP address or domain name. For example: 'localhost', '127.0.0.1', 'example.com', etc.. Not a socket file.