Undefined variable error in PHP. How can I fix it?

Question

I got an error:

Notice: Undefined variable: pollid

What's wrong here?

<?php
    $pollid = $_GET['pollid'];
    $connect = mysqli_connect('localhost', 'root','test','apklausa1');
    $query = "SELECT * FROM polls WHERE pollid='$pollid'";
    $q = mysqli_query($connect, $query);

    while($row = mysqli_fetch_array($q)) {
        $id = $row[0];
        $title = $row[1];
        $pollid = $row[2];
        $ipaddress = $row[3];
        echo "<h1>$title</h1>";
?>

        <table>
            <form action="" method="POST">

<?php
            $questions = "SELECT * FROM questions WHERE pollid='$pollid'";
            $q2 = mysqli_query($connect, $questions);
            while($r = mysqli_fetch_array($q2)) {
            $question = $r[1];
            $votes = $r[2];
            $newvotes = $votes + 1;
            $ip = $_SERVER['REMOTE_ADDR'];
            $newipaddress = $ipaddress."$ip,";

            if (isset($_POST['vote'])) {
                $polloption = $_POST['polloption'];
                if ($polloption == "") {
                    die("You didn't select an option.");
                } else {

                        $ipaddresse = explode(",", $ipaddress);
                        if (in_array($ip, $ipaddresse)) {
                            die("You've already voted");
                        } else {
                    mysqli_query($connect, "UPDATE questions SET votes='$newvotes' WHERE pollid='$pollid' AND question='$polloption'");
                    mysqli_query($connect, "UPDATE polls SET ipaddress='$newipaddress' WHERE pollid='$pollid'");
                    die("You voted Successfully");
                    }
                }
            }

            echo
              '<tr><td>' . $question .
              '</td><td><input type="radio" name="polloption" value="' .
              $question .
              '" /> ' . $votes .
              ' votes</td></tr>';
        }
    }

?>

`$_GET['pollid']` is not defined or have no value – Alive to die - Anant Jun 14 '16 at 08:06 — Alive to die - Anant, Jun 14 '16 at 08:06
can you specify line number – aniket ashtekar Jun 14 '16 at 08:18 — aniket ashtekar, Jun 14 '16 at 08:18

score 0 · Answer 1 · edited Apr 23 '20 at 07:23

0

You need to see where the value of $_GET['pollid'] is coming from.

Probably the error is coming because the variable $pollid is not getting the value. As a result of this it is unset and an error message is getting displayed. Please check the form from where you are making an HTTP GET request. Once the value is received, the problem will be solved.

edited Apr 23 '20 at 07:23

Peter Mortensen

30,738
21
105
131

answered Jun 14 '16 at 08:10

Rajdeep Nandi

25
10

score 0 · Answer 2 · edited Apr 23 '20 at 07:23

0

$_GET['pollid'] is not declared.

There are chances that $_GET and $_POST variables are not declared in some situation. Using isset() helps you to check if the variable is declared or not.

For example,

if(isset($_GET['pollid']))
{
   // Your code here
}

edited Apr 23 '20 at 07:23

Peter Mortensen

30,738
21
105
131

answered Jun 14 '16 at 08:21

FrozenFire

671
14
28

Undefined variable error in PHP. How can I fix it?

2 Answers2