filter out nullable UserID LINQ

Question

HI i want to filter the nullable items out of the groupPhonenumbers, but my linq query doesn't seem to work somehow.

the first method groupPhoneNumbers returns a list of a class with 3 items ( 3 phonenumbers).

results:

[0] --> UserId = "Test_Casper"

[1]---> UserId = ""

[2] --->UserId = ""

// Get all phonenumbers of the group.

var groupPhonenumbers = GroupLogic.GetGroupPhonenumbers(_log, request.requestId, request.sessionId, request.jSessionId, request.ServiceProviderId, request.GroupId, request.Filter, request.StartIndex, request.MaxItems).ToList();

groupPhonenumbers = groupPhonenumbers.Where(gr => (gr.UserId != null) || (gr.UserId != string.Empty)).ToList();

However when i do the where based on a linq query it still shows that twee records, so i;m doing something wrong.

William Snell · Answer

I'm slightly confused about some of your question but I'm going to take a stab at it. I'm assuming that your results collection contains the group phone numbers as well as a UserId that you want to test for empty values. Since UserId is nullable is there any reason to expect an empty string as a value for some entries? I'd try the following... In your first call to get the numbers don't convert it to to a list yet and put the Where clause on it like this: var groupPhonenumbers = GroupLogic.GetGroupPhonenumbers(params).Where(gr => gr.UserId.HasValue); I'd check your string values for empty spaces as well. If your checks for null and an empty string are failing this might be the problem. Actually first just try replacing the checks with string.IsNullOrWhiteSpace(phone) and see if that fixes it.