Undefined variable - Passing a variable through the url

Question

I get cant get my variable to echo on the page even though it shows in the URL. Here is the link that passes it

<a href='eventform.php?$eventname'>

And the code to get it on a other page:

$eventname = 0;
if (isset($_GET['eventname'])) {
$eventname = $_GET['eventname'];
}
echo $_GET['eventname'];

It displays the 0 but not the Mountain 2012 which is in the url at the top. Please help me with this problem

Am i displaying it correctly on the other page?

Quentin · Accepted Answer · 2011-10-03 14:26:58Z

3

You need:

To give it a name in the query string
To sanitise the data for the URI
To sanitise the URI for the HTML

Thus:

<a href='eventform.php?eventname=<?php
    echo htmlspecialchars( urlencode( $eventname ) );
?>'>

answered Oct 3, 2011 at 14:26

Quentin

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2 Comments

SebastianOpperman Over a year ago

It gets rid of the error but it still does not echo the var on the page with my isset code

SebastianOpperman Over a year ago

also the url comes out like this: sportevent/eventform.php?eventname=%3C?php%20%20%20%20echo%20htmlspecialchars(%20urlencode(%20Marathon%202012%20)%20);?%3E

Mathieu Dumoulin · Accepted Answer · 2011-10-03 14:27:08Z

2

You forgot to put eventname= in your url such as:

<a href="eventform.php?eventname=<?php echo $eventname; ?>">

answered Oct 3, 2011 at 14:27

Mathieu Dumoulin

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Comments

Naftali · Accepted Answer · 2011-10-03 14:25:23Z

-1

<a href='eventform.php?<?php=$eventname?>'>

Or:

<a href='eventform.php?<?php echo $eventname?>'>

Although you might want:

<a href='eventform.php?eventname=<?php echo $eventname?>'>

^^sets $_GET['eventname'] to $eventname

answered Oct 3, 2011 at 14:25

Naftali

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2 Comments

Rene Pot Over a year ago

be carefull with echo like that. It might be disabled in the php.ini.

Naftali Over a year ago

@Topener Since PHP 5.4.0, <?= is always available. php.net/manual/en/ini.core.php#ini.short-open-tag

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