Isset¶

isset() is a function that determines if a variable is declared and is different than null.

Isset() is also related to the magic method __isset(), which is used to determine if a property in an object exists or not.

<?php

$var = 'something';

if (isset($var)) {
    echo 'The variable $var contains '.$var;
} else {
    echo 'No such variable as $var';
}
?>

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