Check if Variable is Set or Not PHP

In this tutorial we will learn How To Check if Variable is Set or Not in PHP. PHP isset() function is a built-in function used to check any variable if it has a value or not.

PHP isset() Function

PHP isset() Function checks if a variable is set or not.

In this example we will also use isset() function to check whether a variable is set or not.

Note: When a variable has a value then it is said that variable is set.

<?php
$variable1 = 'HowToCodeSchool.com';
if(isset($variable1))
{
    echo 'Variable1 is set';
}
if(isset($variable2))
{
    echo 'Variable2 is set';
}
else
{
    echo 'Variable2 is not set';
}
?>

In above code, first variable has a value so PHP code will print Variable1 is set.

While in second example, second variable has no value and it is not defined so Variable2 is not set will be output of our code.

Demo

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