Re: [PHP] Re: isset($a->b) even if $a->b = null

the solution has been found. array_key_exists() can actually be used
on objects, and yields the correct result.

http://no.php.net/array_key_exists

thanks to dordea cosmin for pointing this out.

On 17/08/07, Olav Mørkrid <olav.morkrid@xxxxxxxxx> wrote:
the test i need should give the following results:

- FALSE when $a->b does not exist at all
- TRUE when $a->b = null
- TRUE when $a->b = <any value>

empty() gives true for both $a->b = null and not setting any value, so
that's no good.

borokovs suggestion seems to miss the purpose.

anyone else?

On 17/08/07, Colin Guthrie <gmane@xxxxxxxxxxxxxx> wrote:
Olav Mørkrid wrote:
how do i test if a property of a stdclass object is set, even if its
value is null, similar to how array_key_exists() works for arrays.

the following method fails:

$a->b = null;
if(isset($a->b))
echo "yes";

and property_exists() seems only to work for defined objects.

hope someone can help. thanks!

You can try:
unset($a-b)

Or change isset() to empty().

empty() catches more than isset() e.g. '' (empty string), false, 0 etc.
are considered "empty". Depending on your logic it can still be very
useful. It is a language construct rather than a function so it's also
efficient.

Col

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