Distinct ParticipantId

Ramco Ramco

In below code i want only Distinct Participant Id

public List GetSelectedUsers(Int32 ID)
{
try
{
List Result = (from t in context.TrainingParticipants
where t.TrainingID == ID
select t).ToList();
return Result;
}
catch (Exception ex)
{
throw ex;
}
}

Thanks

5 Replies

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Jignesh Kumar4y ago
Accepted answer
Please use this one,
public List GetSelectedUsers(Int32 ID)
        {
            try
            {
                List Result = (from t in context.TrainingParticipants
                                                    where t.TrainingID == ID
                                                    select t).ToList();
                var response = Result.DistinctBy(x => x.ParticipantId).ToList();
                return response;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
Vishal Yelve4y ago
try this
(from t in context.TrainingParticipants where t.TrainingID == ID select t).ToList().Distinct();
Ramco Ramco4y ago
Hi Jignesh

It is giving error Iqueryable TrainingParticipant does not contain a definition for distinctBy

Trying below code but not working

public List GetSelectedUsers(Int32 ID)
{
try
{
List Result = (from t in context.TrainingParticipants
where t.TrainingID == ID
orderby t.ParticipantID select t.ParticipantID).Distinct().ToList();
//select t).Distinct(x => x.ParticipantID).ToList();

return Result;
}
catch (Exception ex)
{
throw ex;
}
}

Thanks
Rajanikant Hawaldar4y ago
test it
List Result = (from t in context.TrainingParticipants
                                                    where t.TrainingID == ID
                                                    select t).ToList().Distinct();
or
List Result = (from t in context.TrainingParticipants
                                                    where t.TrainingID == ID
                                                    select t).ToList().First();
or
List Result = (from t in context.TrainingParticipants
                                                    where t.TrainingID == ID
                                                    select t).ToList().FirstOrDefault();
Jignesh Kumar4y ago
Hi Ramco,

Please use this code it will help you,
public List GetSelectedUsers(Int32 ID)
        {
            try
            {
                List Result = (from t in context.TrainingParticipants
                                                    where t.TrainingID == ID
                                                    select t).DistinctBy(x => x.ParticipantId).ToList();
                return Result;
            }
            catch (Exception ex)
            {
                throw ex;
            }
        }
If you want to disticnt by multiple properties then please use this one,
.DistinctBy(m=> new{m.column1, m.column2})