Check if a json object property is available or not

[nimasdj]

A json object like

 $blah = $a->b->c->d;

this object may or may not have a “d” property. How can I check if “d” property is available or not to avoid notice?

isset($a->b->c->d) 

is something valid?

[Dormilich]

property_exists()

[StarLion]

Mmh… except JSON doesnt have a defined structure. stdObject wont know about properties; so… this doesnt work.

Isset works.

[Dormilich]

@StarLion

except JSON doesnt have a defined structure.

you’re not testing JSON. you’re testing its parsed data.

@StarLion

stdObject wont know about properties;

I doubt that. why shouldn’t an object doesn’t know about its properties?

[StarLion]

@nimasdj

A json object like

@Dormilich

you’re not testing JSON. you’re testing its parsed data.

Uhm… yes. Yes I am?
$a = json_decode(‘{“b”: {“c”: {“d”: 1}}}’);
So, a JSON object. Which is of type stdObject.

property_exists requires a class type as it’s first parameter. What class are you giving it to test?

[Dormilich]

@StarLion

property_exists requires a class type as it’s first parameter. What class are you giving it to test?

Straight from the Manual:

The class name or an object of the class to test for

@StarLion

So, a JSON object. Which is of type stdObject.

From the JSON Standard:

JSON is a text format that facilitates structured data interchange between all programming languages.

besides that:

gettype( json_decode('{"b": {"c": {"d": 1}}}', true) ); // array

not much of an object, if you ask me.

[StarLion]

and yet, it still is, thanks to PHP’s typeshifting.

So, yes, you could do it with property_exists($a->b->c,‘d’). It will work exactly the same as isset, except if d is set to null {‘b’:{‘c’:{‘d’:null}}}, isset says false, property_exists says true, so take whichever fits your requirements better.