可观察的集合“不同”

Question

I have an observable collection displayed in a listView, and I would like it to display agents that have different emails.

If I use.distinct(), all the agents that have, for example, the same first name do not appear. I wish everything BUT mail could be the same (two agents can have the same first name, the same company, but they will have two different emails).

I tried this, but I only get the rows that have all distincts fields, except I would only the emails:

    private ObservableCollection<AgentMailModel> _Agents;
    public ObservableCollection<AgentMailModel> Agents
    {
        get
        {
            return _Agents;
        }
        set
        {
            if (value != _Agents)
            {
                _Agents = value;
                RaisePropertyChanged("Agents");
            }
        }
    }

    foreach (Destinataire dst in (await _dataService.GetDestinatairesAsync()))
            _TmpAgents.Add(new AgentMailModel() { Matricule = dst.Matricule, Nom = dst.Nom, Prenom = dst.Prenom, Mail = dst.Mail });

    foreach (AgentModel ag in (await _dataService.GetAgentsContratsAsync()))
            _TmpAgents.Add(new AgentMailModel() { Matricule = ag.Matricule, Nom = ag.Nom, Prenom = ag.Prenom, Mail = ag.Mail });

    Agents = new ObservableCollection<AgentMailModel(_TmpAgents.Distinct());

I looked at this but I don't know how to use it in my case: LINQ's Distinct() on a particular property

My listView at the moment:

My Database:

as you can see, some rows do not appear, with different mails. I would like to display it.

I would like something like that but doesn't work:

     Agents = new ObservableCollection<AgentMailModel>(_TmpAgents.Select(m => m.Mail).Distinct());

Thanks for your help.

Edit: To be more clear:

Person1: Id=1, Name="Test1", Society = "1", Mail= "Mail1@mail.com"
Person2: Id=2, Name="Test1", Society = "1", Mail= "Mail2@mail.com"
Person3: Id=3, Name="Test1", Society = "1", Mail= "Mail2@mail.com"

How can i get Person1 & Person2 only?

Answer 1

It looks like you are describing a GroupBy here, the only unclear part is that when you group by an email, at some point (as far as I understood from your question) you need only one record, so you should specify which record to take. For example in your above grid, you have two people with the 'pcarre@aeimasso.com' email, just decide which one to pick.

For example here am grouping by email, then ordering each group by name and simply picking the first record:

ObservableCollection<Agent> tmp;
tmp = new ObservableCollection<Agent>(Agents.GroupBy(agent => agent.Email, (key, agent) => agent.OrderBy(e => e.Name).First()));