How to check if an object already exists in collection?

[Ben G]

Hi All,

I am learning programming and my problem is that I have a bunch of objects and I want to add these objects to a list only if the list does not already contain that object. Secondly if the object is already contained I want to ignore that object and add the next one instead. I think I have got the first part working just need some help with part two. Many thanks.

Ben

PartyGroup partyGroup = new PartyGroup(); 
 
using (AseDataReader reader = command.ExecuteReader())
            {
                while (reader.Read())
                {
                    if (!myPartyGroupList.Contains(partyGroup))
                    {
                        partyGroup.PartyGroupID = Convert.ToInt32(reader["party_group_id"]);
                        partyGroup.PartyGroupName = reader["party_group_name"].ToString();
                        partyGroup.PersonList = myPersonList;
 
                        myPartyGroupList.Add(partyGroup);
 
                    }
                    else
                    {
                        //??
 
                    }
 
 
                }
            }

[Plater]

It looks like you're already doing the second part.
If its already in the collection you just ignore it and read the next value from the reader.
Although, I don't know how you go from reader.read() to partygroup

[hype261]

Have you considered using C# SortedSet<T> or HashSet<T> generic collections? They provide the functionality that I believe you are looking for, No duplicate Items.

Here is a link to the MSDN website.

http://msdn.microsoft.com/en-us/library/dd412070.aspx