Question

in sql I have a table like:

PersonOrganisationRole

which has the columns:

PersonId, OrganisationId RoleId

So it’s a three way table between Person, Organisation and Role.

So I was wanting to create a way to get all the Organisations a Person belongs to:

public class Person
{
  public IEnumerable<Organisation> Organisations
        {
            get 
            { 
                var organisations = new List<Organisation>();

                foreach (var personOrganisationRole in PersonOrganisationRoles.Where(personOrganisationRole => !organisations.Contains(personOrganisationRole.Organisation)))
                {
                    organisations.Add(personOrganisationRoles.Organisation);
                }

                return organisations;
            }
        }
}

So I’m basically populating a list by iterating through all items in the table and only adding the org if I haven’t added it already. This is important because there could be multiple rows in the table with the same PersonId and OrganisationId due to the fact a person could have multiple roles at an organisation.

I’m thinking though there must be a far better way of writing this code.

Any suggestions?

Answer 1

A combination of the Linq Select() and Distinct() methods should do it.

 var organisations = PersonOrganisationRoles
              .Select<PersonOrganisationRoles,Organisation>(p => p.Organisation )
              .Distinct();