在列表中获得唯一索引？

Question

The short and simple version is this: I have a database. I have ac# list that I use to interact with that database. Program starts, dump the data into the list, program ends, save it back into the database.

Here's my problem though: I need to make sure that one of my attributes in the list (id) is always unique when I create and remove list items. I was thinking maybe a list might have something similiar to a SQL auto-increment? Or perhaps just a numerical index of which item is in which location?

AddedDependents.Add(new Dependent
                   {
                       IsSpouse = isSpouse,
                       Id = /*unique id/*
                   });

Answer 1

How about generating a Guid ?

Eg

AddedDependents.Add(
    new Dependent
    {
        IsSpouse = isSpouse,
        Id = Guid.NewGuid().ToString("N")
     });

Thus implies that your "Id" is a string, I could not read from your question whether this is possible or not.

Alternatively, do no make it a string, but let it be a Guid type, like:

AddedDependents.Add(
    new Dependent
    {
        IsSpouse = isSpouse,
        Id = Guid.NewGuid()
     });

Answer 2

You could just use the index of the list:

AddedDependents.Add(new Dependent
               {
                   IsSpouse = isSpouse,
                   Id = AddedDependents.Count
               });

Then the Dependent Id and list index are the same so it becomes trivial to get that Dependent from the list.

As mentioned in the comments, if you are likely to delete elements from this list then you can't just get the dependent via the Id, like AddedDependents[dependent.Id] but instead would need to iterate through the list:

AddedDependents.Where(d => d.Id == dependent.Id);