How to check if array variable
$a = array('a'=>1, 'c'=>null);
is set and is null.
function check($array, $key)
{
if (isset($array[$key])) {
if (is_null($array[$key])) {
echo $key . ' is null';
}
echo $key . ' is set';
}
}
check($a, 'a');
check($a, 'b');
check($a, 'c');
Is it possible in PHP to have function which will check if $a['c'] is null and if $a['b'] exist without "PHP Notice: ..." errors?
Use array_key_exists()
instead of isset()
, because isset()
will return false
if the variable is null
, whereas array_key_exists()
just checks if the key exists in the array:
function check($array, $key)
{
if(array_key_exists($key, $array)) {
if (is_null($array[$key])) {
echo $key . ' is null';
} else {
echo $key . ' is set';
}
}
}