Linq to SQL 连接问题

我用 Linq to SQL 添加了一个User表

然后掉用的时候 没有 Connection 

需要在Linq to SQL 里面添加点什么吗?

没分了,多多帮忙啊.

private InfDataContext InitializeInfDataContext_old(IsolationLevel isolationLevel)
        {
            var infDataContext = new InfDataContext(DB_CONNECTION_STRING);
            if (infDataContext.Connection == ConnectionState.Closed)
            {
                infDataContext.Connection.Open();

                infDataContext.Transaction = infDataContext.Connection.BeginTransaction(isolationLevel);
            }

            return infDataContext;
        }