Question

I have a generic list which contains member details and I have a string array of memberIds..I need to filter the list and get the results which contains all the memberIds..How can I achieve this using LINQ.

I tried the following

string[] memberList = hdnSelectedMemberList.Value.Split(',');
_lstFilteredMembers = lstMainMembers.Where(p =>memberList.Contains(p.MemberId))
                                    .ToList();

But the above query is giving me only the results that match the first member ID..so lets say if I have memberIds 1,2,3,4 in the memberList array..the result it returns after the query contains only the members with member ID 1..even though the actual list has 1,2,3,4,5 in it..

Can you please guide me what I am doing wrong.

Thanks and appreciate your feedback.

Answer 1

Strings make terrible primary keys. Try trimming the list:

string[] memberList = hdnSelectedMemberList.Value
                          .Split(',')
                          .Select(p => p.Trim())
                          .ToList();

_lstFilteredMembers = lstMainMembers.Where(p => memberList.Contains(p.MemberId)).ToList();

Because I have a feeling hdnSelectedMemberList may be "1, 2, 3, 4".