NSMutableArray Crash When checking for count

Question

I'm using NSMutableArray with object name myArray : When there is no data from server My mutable array print

In next line of code if check for count it crashes. How to resolve this please help me.

 NSLog(@"Print Array : %@", myArray);
 if(myArray.count > 0 ){

      Excute code
 }

Error:

Print Array : 2015-01-24 10:44:59.852 RemoteAccess[1061:60b] -[NSNull count]: unrecognized selector sent to instance 0x38b21a60

How do you declare, initialize and set myArray? Because it seems like it equals null... — Lyndsey Scott, Jan 24 '15 at 05:29
error says your array is null. check the allocation of array — Ashish Kakkad, Jan 24 '15 at 05:30
@AshishKakkad No, it's not `null`. It's an instance of `NSNull`. Important difference. — rmaddy, Jan 24 '15 at 05:40

score 2 · Answer 1 · answered Jan 24 '15 at 05:33

You think myArray is an array, but it's not - it's an instance of the class NSNull. Most likely, you're pulling it out of a JSON feed, and the JSON isn't returning an array, but rather null.

The simplest fix is to replace your conditional to check what class you actually got:

if ([myArray isKindOfClass:[NSArray class]] && myArray.count > 0) {
   // Do something
}

score -1 · Answer 2 · answered Jan 24 '15 at 05:30

-1

Because your myArray is nil. You have to make sure that myArray is not nil.

answered Jan 24 '15 at 05:30

Lucas Huang

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It isn't `nil`. It's an instance of `NSNull`. – Aaron Brager Jan 24 '15 at 06:03

NSMutableArray Crash When checking for count

2 Answers2