programming languages - In PHP, if a variable does not have a value, why does isset() still return TRUE? -

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here code:

<?php    $ja = '';     if(isset($ja))    echo "cool!";  ?>

i "cool!" when running simple piece of code in browser. learned php.net

isset — determine if variable set , not null

well, in code, did declare variable $ja, didn't add value it, shouldn't "null"?

even though '' seems nothing, still has value (a null character @ end of string).

isset() checks if variable set or not, in case (to ''), is. may want set $ja null first beforehand, instead of setting empty string... or use empty() ;)


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