There is a portential problem with the code involving the variable 'e.OldItems'.
This variable is the result of a method invocation, and the tool is warning that the method
might return a null value, which can cause deferencing a null reference.
It might cause to crash or behave unpredictably.
Therefore, to prevent this, the variable 'e.OldItems' should be checked if it is null or not before use.
{
if (e.Action == NotifyCollectionChangedAction.Add)
{
- foreach (VoiceCommand item in e.NewItems)
- Add(item);
+ if (e.NewItems!= null && e.NewItems.Count > 0)
+ {
+ foreach (VoiceCommand item in e.NewItems)
+ Add(item);
+ }
}
else if (e.Action == NotifyCollectionChangedAction.Remove)
{
- foreach (VoiceCommand item in e.OldItems)
- Remove(item);
+ if (e.OldItems!= null && e.OldItems.Count > 0)
+ {
+ foreach (VoiceCommand item in e.OldItems)
+ Remove(item);
+ }
}
}