Notice: Undefined index: $username

Question

Hello i'm new to php and i wanted to create a admin panel and i got an error with my register page.

This is the error :

Notice: Undefined index: username in C:\wamp\www\Website2 - Copy\register.php on line 18

if (isset($_POST['submit'])){   
    $username = $_POST['username']; // error here
    $password = md5($_POST['password']);
    if(empty($username)or empty($password)){
        echo"There is an empty space";
    }else{
        mysql_query("INSERT INTO users VALUES('', '$username', '$password')");
    }   
}

'username' is not defined in $_POST. try isset($_POST['username']) — DoXicK, Apr 07 '14 at 20:23
Its always good on an insert to specify your columns. That way if you ever need to add fields, your inserts don't all break. `INSERT INTO users (col1, col2....colN) values(....)` — developerwjk, Apr 07 '14 at 20:25
Oh, look, it's unsalted MD5-hashed passwords feat. an SQL injection vulnerability. — Carsten, Apr 07 '14 at 20:26

Rafael Soufraz · Answer 1 · 2014-04-08T14:13:13.717

1

This happens because the empty function checks if the variables $username and $password has no value or set equal to zero. (0, null, false,''). As the empty function does not check if the variable exists, php throws this error.
In this case it would be correct to use the isset function of php.
http://br1.php.net/isset

edited Apr 08 '14 at 14:13

answered Apr 07 '14 at 20:25

Rafael Soufraz

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Notice: Undefined index: $username

1 Answers1