Question

I have a class called Person, which contains various properties such as first name, last name, etc.

I have a List that contains n instances of Person.

List<Person> lstPerson = new List<Person>();

What I need to be able to do is search lstPerson for a given person, and having found that person then obtain the previous and next person relative to the person’s item position in lstPerson.

Person p = lstPerson.Find(delegate(Person o) { return o.FirstName == "Joe"; });

// Then use an accessor to get the previous and next persons
Person prevPerson = p.Previous();
Person nextPerson = p.Next();

Is there a better way to do this then the one that I stated above? What I don’t like about the above solution is that I have to construct the previous and next pointers at the time that I build the Person List.

Answer 1

You could do something like the following:

int personIndex = lstPerson.FindIndex(delegate(Person o) { return o.FirstName == "Joe" });
Person p = lstPerson[personIndex];
// verify that personIndex+1 and personIndex-1 still fall within the list
Person prevPerson = lstPerson[personIndex-1];
Person nextPerson = lstPerson[personIndex+1];