static string DemoTheNewWayOfNullChecking()
{
Contact contact = new Contact();
contact.Name = "Sean";
contact.Phone = "12345678";
contact.Age = 24;
//contact.PersonalPet = new Pet()
//{
// PetName = new PetName()
// {
// Name = "My Pet"
// }
//};
// Maybe class allow you to do something similar to int? for the reference types.
Maybe<Contact> maybeContact = new Maybe<Contact>(contact);
var maybePetName = from c in maybeContact
from cp in c.PersonalPet
from pn in cp.PetName
select pn.Name;
if (maybePetName.HasValue)
return maybePetName.Value;
return null;
}
static string DemoTheOldWayOfNullChecking()
{
Contact contact = new Contact();
contact.Name = "Sean";
contact.Phone = "12345678";
contact.Age = 24;
//contact.PersonalPet = new Pet()
//{
// PetName = new PetName()
// {
// Name = "My Pet"
// }
//};
if (contact == null)
return null;
if (contact.PersonalPet == null)
return null;
if (contact.PersonalPet.PetName == null)
return null;
var petName = contact.PersonalPet.PetName.Name;
if (petName == null)
return null;
return petName;
}