ASP.Net MVC 多个列表从控制器返回答案

【问题标题】：ASP.Net MVC multiple list return from ControllerASP.Net MVC 多个列表从控制器返回
【发布时间】：2013-02-01 04:37:44
【问题描述】：

我正在使用 mvc4 剃须刀，这是第一个型号代码

public class WebLicenses
{
    public string WebLicenseName { get; set; }
    public int CustomerWebLicensesCount { get; set; }
}

public class WebApplication
{
    public string WebApplicationName { get; set; }
    public int Count { get; set; }

    [DisplayFormat(DataFormatString = "{0:dd.MM.yyyy}")]
    public DateTime? EndDate { get; set; }

    public string Never { get; set; }
}
public class griddetail
{
    public griddetail( List<WebLicenses> wl1,List<WebApplication> wa1 )
    { 
        wl =wl1;
        wa = wa1;
    }
    //public List<WebLicenses> wl2 { get; private set; }

    public List<WebLicenses> wl { get; set; }
    public List<WebApplication> wa { get; set; }

}

这是我的第二个模型代码，它使用第一个模型代码作为（这里存储过程返回 2 个表 - WebLicenses，WebApplication（在下面的代码中出现错误 --commented）

public IEnumerable GetOutlookGridDetail(string customerId = "")
{
        List<WebLicenses> weblicenses = new List<WebLicenses>();
        List<WebApplication> webapplication = new List<WebApplication>();            
        griddetail returnValue = new griddetail(weblicenses, webapplication);          

        SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["SLIMConnectionString"].ConnectionString);
        SqlCommand cmd = new SqlCommand("selectCustomerDetail", cn);
        cmd.CommandType = CommandType.StoredProcedure;

        SqlParameter param_CustomerID = new SqlParameter("@CustomerID", SqlDbType.VarChar, 10);
        param_CustomerID.Value = customerId;
        cmd.Parameters.Add(param_CustomerID);

        try
        {
            cn.Open();

            SqlDataReader reader = cmd.ExecuteReader();

            while (reader.Read())
            {
                WebLicenses newRecord = new WebLicenses();
                newRecord.WebLicenseName = Convert.ToString(reader["WebLicenseName"]);
                newRecord.CustomerWebLicensesCount = Convert.ToInt32(reader["CustomerWebLicensesCount"]);
                //returnValue.Add(newRecord);
                weblicenses.Add(newRecord);                    
            }

            reader.NextResult();

            while (reader.Read())
            {
                WebApplication newRecord = new WebApplication();

                newRecord.WebApplicationName = Convert.ToString(reader["WebApplicationName"]);
                newRecord.Count = Convert.ToInt32(reader["Count"]);
                newRecord.Never = Convert.ToString(reader["Never"]);
                webapplication.Add(newRecord);
            }
            returnValue.wl.Add(weblicenses); //here comes error (Argument 1: cannot convert from 'System.Collections.Generic.List<SLIM.Models.WebLicenses>' to 'SLIM.Models.WebLicenses')
        }
        catch (Exception)
        {
            // returnValue = null;
        }
        finally
        {
            cmd.Dispose();

            if (cn.State == ConnectionState.Open)
            {
                cn.Close();
            }
        }

        return returnValue;
}

这是我的控制器代码。

    [HttpPost]
    public ActionResult GridViewPartialView(string recordId)
    {
        IEnumerable result1 = (new SlimHomePageData()).GetRecords(recordId, "");
        IEnumerable result2 = (new SlimHomePageData()).GetRecords();
        List<object> finalResult = new List<object>();
        finalResult.Add(result1);
        finalResult.Add(result2);
        return PartialView("OutlookGridDetail", finalResult);            
    }

我想返回一个包含 2 个列表的列表（但出现上述错误）。还建议，这是正确的方法，因为存储过程返回多个表，我们想通过模型在视图中设置值。

【问题讨论】：

标签： c# asp.net-mvc list return

【解决方案1】：

实例 weblicenses 是 List 类型。看起来它应该是 WebLicenses 的单个实例。

您可能希望将 newRecord 实例添加到 returnValue.wl 列表而不是列表实例。

编辑：您不需要向 wl 列表属性添加任何内容，因为您正在添加到 WebLicenses 列表中。 returnValue 上的 wl 属性是对 WebLicences 实例的引用，因此如果您添加到 WebLicences，那么 wl 将显示相同的添加。

【讨论】：

【解决方案2】：

我忘了给答案，但昨天有人给了减号。是的，时间太长了。我做了什么（我再次解释一切以了解更多）：

第一步：定义2类为

public class WebLicenses
    {
        public int WebLicenseID { get; set; }
        public string WebLicenseName { get; set; }
        public int CustomerWebLicensesCount { get; set; }
        public string CreatedBy { get; set; }
        public string UpdatedBy { get; set; }
    }

public class WebApplication
{
    public int appID { get; set; }
    public string WebApplicationName { get; set; }
    public int Count { get; set; }

    [DisplayFormat(DataFormatString = "{0:dd.MM.yyyy}")]
    public DateTime? EndDate { get; set; }

    public bool Never { get; set; }
    public string CreatedBy { get; set; }
    public string UpdatedBy { get; set; }
}

public class griddetail
{
    public griddetail(List<WebLicenses> wl1, List<WebApplication> wa1)
    {
        weblicences = wl1;
        webapplication = wa1;
    }

    public List<WebLicenses> weblicences { get; set; }
    public List<WebApplication> webapplication { get; set; }        
}

第2步：将控制器更改为

将返回类型 IEnumerable 更改为 griddetail 类

最后在griddetail 类中声明并分配这个嵌套类

public class SlimHomePageData
{
     private SLIMDataContext dc = new SLIMDataContext(ConfigurationManager.ConnectionStrings["SLIMConnectionString"].ConnectionString);
.
.
.

 public IEnumerable GetOutlookGridDetail(string customerId = "")
{
    List<WebLicenses> weblicenses = new List<WebLicenses>();
    List<WebApplication> webapplication = new  List<WebApplication>();            
   //remove from here and add at the end of this method 
   //griddetail returnValue = new griddetail(weblicenses, webapplication);          

   SqlConnection cn = new SqlConnection(ConfigurationManager.ConnectionStrings["SLIMConnectionString"].ConnectionString);
   SqlCommand cmd = new SqlCommand("selectCustomerDetail", cn);
   cmd.CommandType = CommandType.StoredProcedure;

   SqlParameter param_CustomerID = new SqlParameter("@CustomerID", SqlDbType.VarChar, 10);
   param_CustomerID.Value = customerId;
   cmd.Parameters.Add(param_CustomerID);

   try
   {
    cn.Open();

    SqlDataReader reader = cmd.ExecuteReader();

       if (reader.HasRows)
        {
            while (reader.Read())
            {
                WebLicenses newRecord = new WebLicenses();
                newRecord.WebLicenseName = Convert.ToString(reader["WebLicenseName"]);
                newRecord.CustomerWebLicensesCount = Convert.ToInt32(reader["CustomerWebLicensesCount"]);
                weblicenses.Add(newRecord);
            }
        }

        reader.NextResult();
        if (reader.HasRows)
        {
            while (reader.Read())
            {
                WebApplication newRecord = new WebApplication();

                newRecord.WebApplicationName = Convert.ToString(reader["WebApplicationName"]);
                newRecord.Count = Convert.ToInt32(reader["Count"]);

                bool never = false;

                if (reader["Never"] != DBNull.Value)
                {
                    bool.TryParse(reader["Never"].ToString(), out never);
                }

                if (reader["EndDate"] != DBNull.Value)
                {
                    newRecord.EndDate = Convert.ToDateTime(reader["EndDate"]);
                }

                newRecord.Never = never;

                webapplication.Add(newRecord);
            }
        }


    reader.Close();

   }
   catch (Exception)
   {
       // returnValue = null;
   }
   finally
   {
       cmd.Dispose();

       if (cn.State == ConnectionState.Open)
       {
           cn.Close();
       }
   }

       griddetail returnValue = new griddetail(weblicenses, webapplication, webcustomapplication, maintenance, smartcv, histry, doc);
    return returnValue;
   }
  .
   .
  }//closing of my SlimHomePageData class

**第3步：**在ActionMethod中更改为：发布此问题后，我更改了方法，但您可以在上述问题中使用相同的方法概念。稍后我需要另一个类在返回时添加result1。

      public ActionResult GridViewPartialView()
{
          return View();
}


[HttpPost]
        public ActionResult childGridViewPartialView(string recordId, string filtervalue, string flag)
        {
            if (flag == "GridRowChanged")
            {
                IEnumerable result1;
                griddetail result3;
                if (recordId != null)
                {
                    result1 = (new SlimHomePageData()).GetRecords(recordId, "");  //another result to be add later at the end of action method
                    result3 = (new SlimHomePageData()).GetOutlookGridDetail(recordId); //this was in my question
                }
                else
                {
                    result1 = new List<SlimHomePageRecord>();   //another result to be add later at the end of action method
                    result3 = (new SlimHomePageData()).GetOutlookGridDetail(recordId); //this was in my question
                }

                List<object> finalResult = new List<object>();
                finalResult.Add(result1);
                finalResult.Add(result3);
                return PartialView("OutlookGridDetail", finalResult);  
            }
            else
            {
                return PartialView("childGridViewPartialView", (new SlimHomePageData()).GetRecords(null, null));
            }
        }

【讨论】：