PHP Undefined index error. How to fix? [duplicate] - php

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Closed 10 years ago.
Possible Duplicate:
PHP: “Notice: Undefined variable” and “Notice: Undefined index”
I am getting this notice:
PHP Notice: Undefined index: votefor in /home/.../savevote.php on line 2
How can I fix this?
Here is my line 2 in savevote.php:
<?php
$votefor = $_REQUEST["votefor"];
Thank you
Here is the code:
<?php
$votefor = $_REQUEST["votefor"];
// Returns a random RGB color (used to color the vote bars)
function getRandomColor()
{
$r = rand(128,255);
$g = rand(128,255);
$b = rand(128,255);
$color = dechex($r) . dechex($g) . dechex($b);
echo "$color";
}
//Get the IP of the user
$domain = $_SERVER["REMOTE_ADDR"];
$today = date("m/d/Y");
echo "<table id=\"tblResults\" align=\"center\">";
//If votefor is null, then we're just viewing results, so don't log the IP
if ($votefor != "")
{
//Load the addresses XML file
$doc = new DOMDocument();
$doc->load("../vote_dir/xml/addresses.xml");
$addresses = $doc->getElementsByTagName("address");
$pVoted = false;
$pFound = false;
//Loop through the addresses nodes and see if the person has voted before
foreach( $addresses as $address )
{
$lastvisits = $address->getElementsByTagName("lastvisit");
$lastvisit = $lastvisits->item(0)->nodeValue;
$ips = $address->getElementsByTagName("ip");
$ip = $ips->item(0)->nodeValue;
if ($ip == $domain)
{
$pFound = true;
if ($lastvisit == $today)
$pVoted = true;
else
{
$lastvisits->item(0)->nodeValue = $today;
$doc->save("../vote_dir/xml/addresses.xml");
}
break;
}
else
continue;
}
if ($pVoted == true) //Already voted
{
echo "<tr><td colspan=\"3\" class=\"message\">Έχετε ήδη ψηφίσει!</td></tr>";
}
else //Update the XML files
{
if ($pFound == false) //Add new node for IP and date to addresses.xml
{
echo "<tr><td colspan=\"3\" class=\"message\">Ευχαριστούμε που ψηφίσατε!</td></tr>";
$newAddy = $doc->getElementsByTagName('addresses')->item(0);
$newAddressElement = $doc->createElement('address');
$newLastVisitElement = $doc->createElement('lastvisit');
$newAddressElement->appendChild($newLastVisitElement);
$newIPElement = $doc->createElement('ip');
$newAddressElement->appendChild($newIPElement);
$dayvalue = $doc->createTextNode($today);
$dayvalue = $newLastVisitElement->appendChild($dayvalue);
$ipvalue = $doc->createTextNode($domain);
$ipvalue = $newIPElement->appendChild($ipvalue);
$newAddy->appendChild($newAddressElement);
$doc->save("../vote_dir/xml/addresses.xml");
}
else
{
echo "<tr><td colspan=\"3\" class=\"message\">Ευχαριστούμε για την ψήφο σας.</td></tr>";
}
// Update the vote
$doc = new DOMDocument();
$doc->load("../vote_dir/xml/results.xml");
$pollitems = $doc->getElementsByTagName("pollitem");
foreach( $pollitems as $pollitem )
{
$entries = $pollitem->getElementsByTagName("entryname");
$entry = $entries->item(0)->nodeValue;
if ($entry == $votefor)
{
$votes = $pollitem->getElementsByTagName("votes");
$count = $votes->item(0)->nodeValue;
$votes->item(0)->nodeValue = $count + 1;
break;
}
}
$doc->save("../vote_dir/xml/results.xml");
}
}
else
{
echo "<tr><td colspan=\"3\" class=\"message\">Αποτελέσματα Ψηφοφορίας Μέχρι Στιγμής</td></tr>";
}
// Get max vote count
$doc = new DOMDocument();
$doc->load("../vote_dir/xml/results.xml");
$maxvotes = 0;
$pollitems = $doc->getElementsByTagName("pollitem");
foreach( $pollitems as $pollitem )
{
$votes = $pollitem->getElementsByTagName("votes");
$vote = $votes->item(0)->nodeValue;
$maxvotes = $maxvotes + $vote;
}
// Generate the results table
$doc = new DOMDocument();
$doc->load("../vote_dir/xml/results.xml");
$pollitems = $doc->getElementsByTagName("pollitem");
foreach( $pollitems as $pollitem )
{
$entries = $pollitem->getElementsByTagName("entryname");
$entry = $entries->item(0)->nodeValue;
$votes = $pollitem->getElementsByTagName("votes");
$vote = $votes->item(0)->nodeValue;
$tempWidth = $vote / $maxvotes;
$tempWidth = 300 * $tempWidth;
$votepct = round(($vote / $maxvotes) * 100);
echo "<tr><td width=\"20%\" class=\"polls\">$entry</td>";
echo "<td width=\"30%\" class=\"resultbar\"><div class=\"bar\" style=\"background-color: ";
getRandomColor();
echo "; width: $tempWidth px;\">$votepct%</div></td><td width=\"20%\">($vote votes)</td></tr>";
}
echo "<tr><td class=\"total\" colspan=\"3\">$maxvotes άτομα ψήφισαν μέχρι τώρα.</td>";
echo "</table>";
?>
#Brian
<script language="javascript">
function setVote(voteName)
{
document.getElementById("votefor").value = voteName;
}
function confirmSubmit()
{
if (document.getElementById("votefor").value == "")
{
var agree=confirm("Παρακαλώ επιλέξτε μια απάντηση, για να ψηφίσετε");
return false;
}
}
</script>

Answer 1

The request parameter isn't being passed. If you know why it might be missing and just want to prevent the notice, you can say:
$votefor = isset( $_REQUEST["votefor"] ) ? $_REQUEST["votefor"] : null;

Answer 2

It is not safe to use $_REQUEST because it can be $_GET or $_POST, better is specify which you want.
At second you need to check if the array key exists. This can officially be done with array_key_exists(). But unfortunately this function is a little bit slow. You can replace it by using the isset() function, but this says a null value is not set and returns false when it is null. The best approach is to use them both, first the isset and then the array_key_exists:
<?php
if (isset($_POST['votefor']) || array_key_exists($_POST['votefor'])) {
// do something
}
?>
Or use only isset if you are sure the value won't be null.
If you are almost 100% sure the index votefor exists in the array you need to debug it. var_dump the $_REQUEST array to see which items (and indexes) are in there and look what you did wrong.

Answer 3

1/ Check you have a request parameter named votefor
2/ Check you didn't misspelt it

Answer 4

Handle it like so:
if(array_key_exists("votefor", $_REQUEST)) {
...
}

Answer 5

You may ignore notice reports by setting error_reporting no to show them
error_reporting(E_ALL & ~E_NOTICE);