compare two list and return not matching items using linq

Question

i have a two list

List SentList;
List MsgList;

both have the same property called MsgID;

MsgList            


        

Answer 1

Try,

  public class Sent
{
    public int MsgID;
    public string Content;
    public int Status;

}

public class Messages
{
    public int MsgID;
    public string Content;
}

  List SentList = new List() { new Sent() { MsgID = 1, Content = "aaa", Status = 0 }, new Sent() { MsgID = 3, Content = "ccc", Status = 0 } };
            List MsgList = new List() { new Messages() { MsgID = 1, Content = "aaa" }, new Messages() { MsgID = 2, Content = "bbb" }, new Messages() { MsgID = 3, Content = "ccc" }, new Messages() { MsgID = 4, Content = "ffffd" }, new Messages() { MsgID = 5, Content = "eee" }};

            int [] sentMsgIDs = SentList.Select(v => v.MsgID).ToArray();
            List result1 = MsgList.Where(o => !sentMsgIDs.Contains(o.MsgID)).ToList();

Hope it should help.