How to use flags enums in Linq to Entities queries?

Question

I have a [Flags] enum like this:

[Flags]
public enum Status
{
  None = 0,
  Active = 1,
  Inactive = 2,
  Unknown = 4
}

A Status enum may c

Answer 1

I don't know EF, but could inserting additional casts work?

var result = from r in db.Records
             where ((byte)r.Status & (byte)s) == (byte)r.Status
             select r

Answer 2

Take a look at the following good post, it shows you the following alternatives:

• At least one of the selected flags set
• Exactly the same flags set
• At least those flags you selected and more

https://timdams.wordpress.com/2011/02/14/using-enum-flags-to-write-filters-in-linq/#comment-30

Answer 3

Just use HasFlag()

var result = from r in db.Records
         where r.Status.HasFlag(s)
         select r

Answer 4

The folloiwng works for me in C#

    public const StatusTypes ActiveAlert = StatusTypes.Accepted | StatusTypes.Delivered;

        int flags = (int)ActiveAlert;

        try
        {
            var query = from p in model.AlertsHistory
                        where (p.UserId == clientId
                        && (p.Status.HasValue && (p.Status.Value & flags) != 0))
                        select p;
            var aList = query.ToList();

            return (aList);


        }
        catch (Exception exc)
        {
            log.Error("Exception getting Alerts History for user.", exc);
            throw;
        }

Answer 5

In DB Flags enum must be integer. After that you can try it like this:

Status s = Status.Active | Status.Unknown;

var result = from r in db.Records
where (s & r.Status) == r.Status
select r

Answer 6

Try it like this:

byte status = (byte)(Status.Active | Status.Unknown);

var result = from r in db.Records
             select r
             where (r.Status & status) != 0