PHP - Checking if array index exist or is null

Question

Is there a way to check if an array index exists or is null? isset() doesn't tell you whether the index doesn't exist or exists but is null. If I do : isset($array[$index]) || is_null($array[$index]) it won't work because if the index doesn't exist is_null will crash.

How can I check this please? Also is there a way to check only if something exist, no matter if it is set to null or not?

Answer 1

The function array_key_exists() can do that, and property_exists() for objects, plus what Vineet1982 said. Thanks for your help.

Answer 2

This is the very good question and you can use get_defined_vars() for this:

$foo = NULL; $a = get_defined_vars();  if (array_key_exists('def', $a)) {    // Should evaluate to FALSE  };   if (array_key_exists('foo', $a)) {    // Should evaluate to TRUE }; 

This will solve your problem