reset the entities state on a Entity Framework Db Context

DbContextExtensions.cs

public static class DbContextExtensions
{
  public static void Reset(this DbContext context)
  {
      var entries = context.ChangeTracker
                           .Entries()
                           .Where(e => e.State != EntityState.Unchanged)
                           .ToArray();

      foreach (var entry in entries)
      {
          switch (entry.State)
          {
              case EntityState.Modified:
                  entry.State = EntityState.Unchanged;
                  break;
              case EntityState.Added:
                  entry.State = EntityState.Detached;
                  break;
              case EntityState.Deleted:
                  entry.Reload();
                  break;
          }
      }
  }
}