if (command.CommandText.ToLower().StartsWith("insert", StringComparison.InvariantCultureIgnoreCase) == false)
          {
              // 判断当前会话是否处于分布式事务中
              bool isDistributedTran = Transaction.Current != null &&
                                       Transaction.Current.TransactionInformation.Status !=
                                       TransactionStatus.Committed;
              foreach (var context in interceptionContext.DbContexts)
              {
                  //判断该 context 是否处于普通数据库事务中
                  bool isDbTran = context.Database.CurrentTransaction != null;
 
                  // 如果处于分布式事务或普通事务中，则“禁用”读写分离，处于事务中的所有读写操作都指向 Master
                  string connectionString = isDistributedTran || isDbTran ? this.MasterConnectionString : this.SlaveConnectionString;
                  if (command.Connection.State == ConnectionState.Open)
                  {
                      command.Connection.Close();
                  }
                  command.Connection.ConnectionString = connectionString;
                  command.Connection.Open();
              }
          }