Question

I have an app making a request to a JSON on a server to fetch some data . All works fine until
the value for a field in the JSON has the null value . Then the app crashes .
So I get the data , put it in a NSDictionary , and then access all the values in that dictionary . I’ve tried with those if() statements but still , if the value is null , the app crashes .

            if([item valueForKey:@"title"]!=NULL)
            [sbcvItem setTitle:[item valueForKey:@"title"]];
            if([item valueForKey:@"desc"]!=NULL)
            [sbcvItem setDesc:[item valueForKey:@"desc"]];
            if([item valueForKey:@"url"]!=NULL)
            [sbcvItem setUrl:[item valueForKey:@"url"]];

Any suggestion is welcome .

Answer 1

Neither NSDictionary nor NSArray can store nil (or NULL) as a value. Instead, we use a placeholder object. That placeholder object is a singleton of class NSNull, and you get a pointer to it using [NSNull null]. So you need to test like this:

if ([item objectForKey:@"title"] != [NSNull null])
    [sbcvItem setTitle:[item objectForKey:@"title"]];