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How to check if variable is defined in PHP



229 views
asked Jul 23, 2018 by avibootz
retagged Jun 3, 2025 by avibootz
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1 Answer

0 votes 
$test = NULL;
$vars = get_defined_vars();
if (array_key_exists('test', $vars)) 
    echo "yes";
else
    echo "no";

/*
run:

yes

*/

 



answered Jul 23, 2018 by avibootz
edited Jul 23, 2018 by avibootz

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