GetHashCode on null fields?

Question

How do I deal with null fields in GetHashCode function?

Module Module1
  Sub Main()
    Dim c As New Contact
         


        

Answer 1

Typically, you check for null and use 0 for that "part" of the hash code if the field is null:

return (Name == null ? 0 : Name.GetHashCode()) ^ 
  (Address == null ? 0 : Address.GetHashCode());

(pardon the C#-ism, not sure of the null check equivalent in VB)