1. Leverage the solution created earlier in this chapter and add a class called UpdateActivity.
2. Import the following namespaces:

using System; 
using System.Collections.Generic; 
using System.Linq; 
using Microsoft.Xrm.Sdk; 
using Microsoft.Xrm.Tooling.Connector; 
using Packt.Xrm.Entities; 
using Microsoft.Crm.Sdk.Messages; 

3. Initialize a service context and IOrganizationService at the class scope level:

OrganisationServiceContext _organizationContext;
IOrganizationService _organizationService; 

4. Add a GetEmails method that takes a Guid as a parameter:

public IEnumerable<Email> GetEmails(Guid parentEntityId) 
{ 
var query = from email in _organizationContext.EmailSet 
         where email.RegardingObjectId.Id == parentEntityId 
                && 
                email.StateCode == EmailState.Open 
                select new Email 
                { 
                  Id = email.Id, 
                  Subject = email.Subject 
       }; 

return query.ToList(); 
} 

5. Add a closeEmailAsCancelled method that takes an e-mail as a parameter:

public void CloseEmailAsCancelled(Email email) 
{ 
    email.StateCode = EmailState.Canceled; 

    var setStateRequest = new SetStateRequest() 
    { 
        Status = new OptionSetValue((int)email_statuscode.Canceled), 
        State = new OptionSetValue((int)EmailState.Canceled), 
        EntityMoniker = new EntityReference(Email.EntityLogicalName, email.Id) 
    }; 
    _organizationContext.Execute(setStateRequest); 
} 

6. Add an UpdateEntity method that takes an entity as a parameter:

public void UpdateEntity(Entity entity) 
{ 
_organizationContext.UpdateObject(entity); 
} 

7. Add a Commit() method that calls the SaveChanges on the context:

public void Commit() 
{ 
_organizationContext.SaveChanges(); 
}