CRM Late Bound - Cleaner Approach - console-application

Question

I have the following code and I'm trying to find a more elegant approach to this. activityParty is a DataCollection. I am basically trying to get a list of recipients for an email, which can be of type users or contacts.
I am familiar with early bound but in this scenario must use late bound.
Is there a better approach to this?
var recipientParty = activityParty.Where(x => x.GetAliasedValueOrDefault<OptionSetValue>("ap.participationtypemask").Value == 2).ToList();
var recipientList = new List<string>();
foreach (var to in recipientParty)
{
if (to.Attributes.Contains("u.internalemailaddress"))
{
recipientList.Add(to.GetAliasedValueOrDefault<string>("u.internalemailaddress"));
}
if (to.Attributes.Contains("c.emailaddress1"))
{
recipientList.Add(to.GetAliasedValueOrDefault<string>("c.emailaddress1"));
}
}

Answer 1

Have a look at AddressUsed property of ActivityParty entity. It should contain email address, regardless which entity is source of party involved.
So, in your code you can use to.AddressUsed instead whole if {...} statement.

Answer 2

Try this:
using (var serviceContext = new OrganizationServiceContext(this.OrganizationService)) // if you are writing custom code activity
//using (var serviceContext = new OrganizationServiceContext(localContext.OrganizationService)) // if you are writing plugin
{
var activityPartySet = serviceContext.CreateQuery<ActivityParty>();
var activityParties = activityPartySet.Where(
ap => ap.PartyId != null &&
ap.ParticipationTypeMask != null &&
ap.ParticipationTypeMask.Value == 2).ToList();
var userSet = serviceContext.CreateQuery<SystemUser>();
var contactSet = serviceContext.CreateQuery<Contact>();
var recipientList = new List<string>();
foreach (var ap in activityParties)
{
var partyRef = ap.PartyId;
if (partyRef.LogicalName == SystemUser.EntityLogicalName)
{
var user = (from u in userSet
where u.Id == partyRef.Id
select new SystemUser
{
InternalEMailAddress = u.InternalEMailAddress
}).FirstOrDefault();
if (user != null)
recipientList.Add(user.InternalEMailAddress);
}
else if (partyRef.LogicalName == Contact.EntityLogicalName)
{
var contact = (from c in contactSet
where c.Id == partyRef.Id
select new Contact
{
EMailAddress1 = c.EMailAddress1
}).FirstOrDefault();
if (contact != null)
recipientList.Add(contact.EMailAddress1);
}
}
}
Hope it helps!