Undefined variable on POST

Question

I looked trough your pages and fixed my undefined index on username and password but now I get undefined variable. I had more code but decided to simplify it for the sake of testing and just echo it to see if anything changes and it doesn't.

<?php
if (isset($_POST['submit'])){
$uname = isset($_POST['username']);             
$pass = isset($_POST['password']); 
}

echo $uname;
echo $password;
?>

I get this:

Notice: Undefined variable: uname in C:\xampp\htdocs\8\login.php on line 7

Notice: Undefined variable: pass in C:\xampp\htdocs\8\login.php on line 8

I do not really understand what's wrong here. If needed here is my form page html.

<form id="login" method="post" action="login.php">
<div id="loginon">
<label for="username" style="color:#0F0; font-family:Arial, Helvetica, sans-serif;" >Username: &nbsp; &nbsp;</label>
<input type="text" id="username" name="username" />
<br  />
<br  />

<label for="password"  style="color:#0F0; size:auto; font-family:Arial, Helvetica, sans-serif;">Password: &nbsp; &nbsp;</label>
<input type="password" id="password" name="password" /> 
<br />
<br />
<input type="image" src="http://www.clker.com/cliparts/2/G/4/v/K/E/submit-hi.png" border="0" width="180px" height="80px" alt="Submit" />
</div>
</form>
</body>

EDIT: The further problem is connected to this so I think I am allowed to post it here.

if($username == "pikachu" || "cloud") {
    $ucheck = "dobar";
} else {
    $ucheck = "los";
}

if ($password == "123123" || "132132") {
    $pcheck = "topar";
} else {
    $pcheck = "losh";
}

if($ucheck == "dobar" && $pcheck == "topar") {
    echo "Najjaci si!";

}

elseif ($ucheck == "dobar" && $pcheck == "losh") {
    echo "Wimp.";
} elseif ($ucheck == "los" && $pcheck == "topar") {
    echo "Fish.";
}

The problem is that it always echoes out "Najjaci si" no matter what I type in the previous form. Any ideas?

If I do that, I get "Notice: Undefined variable: password in C:\xampp\htdocs\8\login.php on line 9" — victiMusPrime, Jun 25 '15 at 10:38
@victiMusPrime check variable `$pass` and `$password`...you are using two different variable — Prafulla, Jun 25 '15 at 10:40
I get a blank page now, which means that the form data doesn't come to the page. Jonas m has the solution but thank you all for the effort. — victiMusPrime, Jun 25 '15 at 10:47
possible duplicate of [PHP: "Notice: Undefined variable" and "Notice: Undefined index"](http://stackoverflow.com/questions/4261133/php-notice-undefined-variable-and-notice-undefined-index) — , Jun 25 '15 at 10:47

Jonas m · Accepted Answer · 2015-06-25T10:38:17.540

2

Since you have the variable decleration inside a logic (If), there is a chance that the variables are not set at all. Try this

<?php
if (isset($_POST['submit'])){
  $uname = isset($_POST['username']);             
  $pass = isset($_POST['password']); 

  echo $uname;
  echo $pass;
} else {
  echo "No submit detected!";
}


?>

It also doesen't look like if you have an actual element named submit. Try adding this:

<input type="submit" name="submit" value="Send my form" />

Now, your form contains an element named "submit" which will be send as a post parameter when the form is submitted.

I myself, in need of a framework, like doing like this:

$username = ( isset($_POST["username"]) && $_POST["username"] != "" ? $_POST["username"] : false );
$password = ( isset($_POST["password"]) && $_POST["password"] != "" ? $_POST["password"] : false );

if( !$username === false && !$password === false )
{
    echo $username . " <br /> " . $password;
} else {
    echo "No! :) ";
}

edited Jun 25 '15 at 10:38

answered Jun 25 '15 at 10:32

Jonas m

2,646
3
22
43

It echoes "No submit detected!" – victiMusPrime Jun 25 '15 at 10:36
Because you need to add a submit-button to your html form. Have a look at my answer. – Jonas m Jun 25 '15 at 10:39
Oooooh, so it was the submit button that was causing the whole problem? Thanks, I have it all sorted out now. :) – victiMusPrime Jun 25 '15 at 10:46
Yes it was. Because you were only setting the variables, if the key "submit" was set in the POST array. It were not, since nothing with the name "submit" were posted :) – Jonas m Jun 25 '15 at 10:51
You are writing: if($username == "pikachu" || "cloud") It should be if($username == "pikachu" || $username == "cloud") You need the variable you want to check up against on all "OR's"/"Ands" – Jonas m Jun 25 '15 at 11:18
Jonas m tried this now, It doesn't display anything. – victiMusPrime Jun 25 '15 at 11:30

Narendrasingh Sisodia · Answer 2 · 2015-06-25T10:38:48.820

1

isset will check that variable is set or not and pass value in 0 or 1. So over here you need to do as

$uname = isset($_POST['username']) ? $_POST['username'] : '';             
$pass = isset($_POST['password']) ? $_POST['password'] : '';

Notice: Undefined variable: pass in C:\xampp\htdocs\8\login.php on line 8

Its because you were echoing $password instead of $pass

Edited

Do it as

$uname = '';
$pass = '';

if (isset($_POST['submit'])){
$uname = isset($_POST['username']);             
$pass = isset($_POST['password']); 
}

echo $uname;
echo $pass;

edited Jun 25 '15 at 10:38

answered Jun 25 '15 at 10:32

Narendrasingh Sisodia

21,247
6
47
54

Still getting the same error after trying your fix. Any other clues? – victiMusPrime Jun 25 '15 at 10:35
Check first is it getting within `if` condition – Narendrasingh Sisodia Jun 25 '15 at 10:39

score 0 · Answer 3 · answered Jun 25 '15 at 10:58

Try this

In form

<form id="login" method="post" action="login.php">
    <div id="loginon">
        <label for="username" style="color:#0F0; font-family:Arial, Helvetica, sans-serif;" >Username: &nbsp; &nbsp;</label>
        <input type="text" id="username" name="username" />
        <br  />
        <br  />

        <label for="password"  style="color:#0F0; size:auto; font-family:Arial, Helvetica, sans-serif;">Password: &nbsp; &nbsp;</label>
        <input type="password" id="password" name="password" />
        <br />
        <br />
        <input type="submit" name="submit"/>
    </div>
</form>
</body>

In login.php

<?php
    if (isset($_POST['submit']))
    {
        $uname = $_POST['username'];
        $pass = $_POST['password'];
    }

    echo $uname;
    echo $pass;
?>

Undefined variable on POST

3 Answers3