集合返回

Question

使用时，我很难从一个函数中获取两个记录 采集。我不知道自己在做什么错，在此先感谢您 帮助。

服务调用功能...

Announcements announcements = new Announcements(ID, moduleID, _config, _logger);

return announcements;  // this does not contain anything although Announcements load functions has two record

namespace Api.Collection
{
    public class Announcements : List<Announcement>
    {
        IConfiguration _config;
        ILoggerManager _logger;

        private string _uspGetAnnouncement = "storedproced_GetAnnouncemnt";

        public List<Announcement> announcements = new List<Announcement>();
        public Announcements()
        {

        }
        public Announcements(int employeeID, int moduleID, IConfiguration config, ILoggerManager logger)
        {
            _config = config;
            _logger = logger;

            if (employeeID > 0 && moduleID > 0)
            {
                Load(employeeID, moduleID);
            }
        }

        public virtual void Load(int employeeID, int moduleID)
        {     
            List<SqlParameter> lParam = new List<SqlParameter>();

            Util.DataUtil dataUtil = new Util.DataUtil(_config);
            SqlParameter param;

            if (employeeID > 0 && moduleID > 0)
            {
                param = new SqlParameter("@employeeID", employeeID);
                lParam.Add(param);

                param = new SqlParameter("@moduleID", moduleID);
                lParam.Add(param);
            }

            DataTable dt = Util.GetDataTable(_uspGetAnnouncement, lParam.ToArray());

            if (dt.Rows.Count > 0)
            {
                foreach (DataRow dr in dt.Rows)
                {
                    announcements.Add(new Announcement(dr, dt.Rows.Count, _config, _logger));
                }
            }
            return announcements;   *** this has 2 records
        }
    }
}

Answer 1

朋友评论可能是正确的，但我不知道您的用例，因此也许是有效的。 就像其他评论/回答中所述，Load方法不返回任何内容，因此您的行

return announcements;

什么都不做。 您实际上是将项目添加到您拥有的内部列表中。 因此，我猜测您当前的代码，这将有助于向您显示服务代码中的两个项目。

Announcements announcements = new Announcements(ID, moduleID, _config, _logger);
return announcements.announcements;

显然，这看起来令人困惑，而且不是您想要的。由于您是从List继承而来，因此您需要在Load函数中将各项添加到自身中。因此，我相信以下代码会起作用。关键是只使用“添加”而不是“公告”。添加

namespace Api.Collection
{
public class Announcements : List<Announcement>
{
    IConfiguration _config;
    ILoggerManager _logger;

    private string _uspGetAnnouncement = "storedproced_GetAnnouncemnt";

    public Announcements()
    {

    }
    public Announcements(int employeeID, int moduleID, IConfiguration config, ILoggerManager logger)
    {
        _config = config;
        _logger = logger;

        if (employeeID > 0 && moduleID > 0)
        {
            Load(employeeID, moduleID);
        }
    }

    public virtual void Load(int employeeID, int moduleID)
    {     
        List<SqlParameter> lParam = new List<SqlParameter>();

        Util.DataUtil dataUtil = new Util.DataUtil(_config);
        SqlParameter param;

        if (employeeID > 0 && moduleID > 0)
        {
            param = new SqlParameter("@employeeID", employeeID);
            lParam.Add(param);

            param = new SqlParameter("@moduleID", moduleID);
            lParam.Add(param);
        }

        DataTable dt = Util.GetDataTable(_uspGetAnnouncement, lParam.ToArray());

        if (dt.Rows.Count > 0)
        {
            foreach (DataRow dr in dt.Rows)
            {
                Add(new Announcement(dr, dt.Rows.Count, _config, _logger));
            }
        }
    }
}
}

Answer 2

不确定是否可行。

    namespace Api.Collection
{
    public class Announcements : List<Announcement>
    {
        IConfiguration _config;
        ILoggerManager _logger;

        private string _uspGetAnnouncement = "storedproced_GetAnnouncemnt";

        public List<Announcement> announcements = new List<Announcement>();
        public Announcements()
        {

        }
        public Announcements(int employeeID, int moduleID, IConfiguration config, ILoggerManager logger)
        {
            _config = config;
            _logger = logger;

            if (employeeID > 0 && moduleID > 0)
            {
                var value = Load(employeeID, moduleID);
            }
        }

        public virtual List<Announcement> Load(int employeeID, int moduleID)
        {     
            List<SqlParameter> lParam = new List<SqlParameter>();

            Util.DataUtil dataUtil = new Util.DataUtil(_config);
            SqlParameter param;

            if (employeeID > 0 && moduleID > 0)
            {
                param = new SqlParameter("@employeeID", employeeID);
                lParam.Add(param);

                param = new SqlParameter("@moduleID", moduleID);
                lParam.Add(param);
            }

            DataTable dt = Util.GetDataTable(_uspGetAnnouncement, lParam.ToArray());

            if (dt.Rows.Count > 0)
            {
                foreach (DataRow dr in dt.Rows)
                {
                    announcements.Add(new Announcement(dr, dt.Rows.Count, _config, _logger));
                }
            }
            return announcements;   *** this has 2 records
        }
    }
}

我希望澄清一下。...

问候