private void CheckStringWrite()
 {
     using (var db = new AppDb())
     {
         var itm = new TableStringType
         {
             StrField = this.GetType().ToString()
         };
         db.TableStringType.Add(itm);
         db.SaveChanges();
     }
 }
        private void CheckStringReadWrite()
        {
            using (var db = new AppDb())
            {
                var itm = new TableStringType
                {
                    StrField = this.GetType().ToString()
                };
                db.TableStringType.Add(itm);
                db.SaveChanges();

                var uid = db.TableStringType.OrderByDescending(x => x.Id).FirstOrDefault();
                Assert.Equal(uid.StrField, this.GetType().ToString());
            }
        }