c# - Can't check if a specific object key is null

Question

I have this object:

var obj = JsonConvert.DeserializeObject<RootObject>(responseText);

now in some case the deserialization generate two key: arts and det. The det key is even filled, but in some cases the key arts could be null. I check the object content null like this:

foreach(var item in obj.det){
   ...
   if(!item.arts.Equal(null)){ 'the problem is here
    ...
   }
}

The problem is on the condition, in particular I check if the arts key is different against null but I got this exception:

NullReference Exception was not managed

I don't understand what I did wrong, could someone enlight me?

Answer 1

Try

if(item.arts == null){
 // do your checking operation
}

I am not sure if that is causing your problem but in general calling a method on a null object creates an error.