Unidentified index while echoing out else - php

Question

I'm new to PHP and i've been learning PhP like a week ago so please bear with me.
While i was trying to echo out an else statement if any variable in the POST request is different or not set.
<form action="process.php" method="POST">
<p> <input type="radio" name="language" value="PHP"> PHP <br>
<input type="radio" name="language" value="RUBY"> RUBY <br>
<input type="radio" name="language" value="HTML"> HTML <br>
</p>
<input type="Submit" value="Submit">
</form>
process.php
<?php
$lang = $_POST['language'];
if (isset($lang)) {
echo $lang;
}
else {
echo 'Buzz off';
}
?>
While its showing error like :
Notice: Undefined index: language in
/Applications/XAMPP/xamppfiles/htdocs/process.php on line 2
Please help :)

Answer 1

You're trying to get an undefined array index and put it into a variable, and this will throw an exception.
You should check if the array key isset before you try to put it in a variable, like this:
if ($_POST['language']) {
$lang = $_POST['language'];
echo $lang;
}
else {
echo 'Buzz off';
}
If you are using PHP7, you can use the Null coalescing operator.
$lang = $_POST['language'] ?? 'Buzz off';
echo $lang;