iOS checking if JSON return has Key

Question

I'm using NSJsonSerialization to get back a json return after I POST something. I either get back my correct return or I get:

{
"status":"false"
}

I need to check if I got back my return before I try to parse it (since it crashes if the Keys I ask for don't exist) However if I check against

[whatever objectForKey:@"status"] == nil

When it is nil it's ok, however if it does not exist it crashes (because I got back my other return)

The crash I get is this one, it seems NSJSONSerialzation is returning a NSArray as a NSdictionary?:

2012-07-02 11:03:40.426 [9412:10703] -[__NSArrayM objectForKey:]: unrecognized selector sent to instance 0x75f03f0
2012-07-02 11:03:40.429 [9412:10703] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSArrayM objectForKey:]: unrecognized selector sent to instance 0x75f03f0'

I need to figure out a way to know which return I got so I can act accordingly.

Answer 1

you could check the type of whatever variable

if([whatever isKindOfClass:[NSDictionary class]])
    //then check for nil
else
    //Then its not a dictionary then in your case its empty