Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

PHP Build a Simple PHP Application Creating the Menu and Footer Adding Active States to the Navigation

Posted by Ivan Tomicic
Ivan Tomicic
3,873 Points

What if there is no variable in page?

Ok I tried to work on this task and if I don't set any variable to index.php browser gives me an error, how can I tell it just not to show anything in code if there is no variable? I tried with else function but no luck?

1 Answer

miguelcastro2
miguelcastro2
Courses Plus Student 6,573 Points 
// Check to see if a variable is set
if (isset($my_variable)) {
   echo 'Set';
} else {
   echo 'Not Set';
}
Ivan Tomicic
Ivan Tomicic
3,873 Points

Ok, but I need to check for variable too, is there a shorter way than this

<?php
if (isset($section)) {
if ($section == "shirts") { 
echo 'on'; 
}
} 
else { 
echo ''; 
} 
?>
miguelcastro2
miguelcastro2
Courses Plus Student 6,573 Points

In this IF clause, if the first condition is TRUE, meaning that the variable $section is set, then it will check the second condition to see if $section == "shirts".

if (isset($section) && $section == "shirts") {
   echo 'on'; 
} else { 
   echo ''; 
}
Ivan Tomicic
Ivan Tomicic
3,873 Points

Thank you!

Jason Anello
Jason Anello
Courses Plus Student 94,610 Points

Hi Ivan,

This was the code I used if you want to compare to your own:

<li class="shirts<?php if ( isset($section) && $section == "shirts") { echo " on"; } ?>"><a href="shirts.php">Shirts</a></li>
<li class="contact<?php if ( isset($section) && $section == "contact") { echo " on"; } ?>"><a href="contact.php">Contact</a></li>

There's no need to have the else block where you echo out an empty string.

Ivan Tomicic
Ivan Tomicic
3,873 Points

Oh, thank you, that is useful :)