在实体框架中将 GridView 与存储过程结果绑定

Question

我已将存储过程的结果（在实体框架中）存储在 IList 中，然后将我的网格与此 IList 绑定。当此结果为空时，网格没有任何列，但我需要在网格中显示这些列。有没有办法解决这个问题？

这是我的代码：

IList list = new ArrayList();

try
{
    var context = new SabzNegar01Entities1();

    list = (from p in context.tbl_ReturnSalesFactor_D
            let add = (p.MainNum * p.Fee)
            let pureAdd = ((p.MainNum * p.Fee) - (p.MainNum * p.Discount)) + ((p.Tax + p.Charges) * p.MainNum)
            let taxChange = (p.Tax + p.Charges) * p.MainNum
            let discount = p.Discount * p.MainNum
            where p.DocNo == inDocNo
            select new { p.Row, p.StockCode,  p.tbl_Stock.PDescription, p.Fee, p.MainNum, add, taxChange, discount, pureAdd }).ToList();
}
catch (Exception ex)
{
    PMessageBox.Show(ex.Message, "Error in Reading  ReturnSalesFactor_Details Data");
}

和绑定：

radGridView_Product.DataSource = list ;

Answer 1

我会这样做：

• 定义一个与您从存储过程中返回的数据相匹配的 C# 类（例如 SalesInfo 或任何您想调用的名称）

• 然后将您的IList 定义为List<SalesInfo>（请不要再使用糟糕的旧ArrayList！）

• 当您调用存储过程但没有返回任何值时，您只需在返回的列表中添加一个虚拟的 SalesInfo 条目，例如有no data found作为它的描述，其他都是空的/0.0

这样，您的方法将始终返回至少一个元素，并且由于该元素在那里，gridview 知道它的列以及如何调用它们

更新：

我会首先定义一个类来保存您想要在 gridview 中显示的所有属性：

// just a data container to hold the information - call it whatever you like!
// also: with the datatypes, I am just *GUESSING* because you didn't exactly tell us
// what those values are - adapt as needed !
public class SalesInfo
{
    public int Row { get; set; }
    public string StockCode { get; set; }
    public string Description { get; set; }
    public decimal Fee { get; set; }
    public decimal MainNum { get; set; }
    public decimal Add { get; set; }
    public decimal TaxChange { get; set; }
    public decimal Discount { get; set; }
    public decimal PureAdd { get; set; }
}

接下来，定义一个从存储过程中获取数据的方法 - 如果没有返回数据，则添加一个虚拟条目：

// Define a method to return an IList of that data container class defined above
public IList<SalesInfo> GetSalesInfo()
{
    // please, as of .NET 2.0 - use the List<T> and stop using ArrayList!
    IList<SalesInfo> list = new List<SalesInfo>();

    try
    {
        // put your context usage into using()..... blocks to ensure proper disposal
        using (var context = new SabzNegar01Entities1())
        {
             // fetch the data, turn it into SalesInfo records
             list = (from p in context.tbl_ReturnSalesFactor_D
                     where p.DocNo == inDocNo
                     select new SalesInfo
                            {
                                Row = p.Row,
                                StockCode = p.StockCode,
                                Description = p.tbl_Stock.PDescription,
                                Fee = p.Fee,
                                MainNum = p.MainNum,
                                Add = p.MainNum*p.Fee,
                                PureAdd = ((p.MainNum*p.Fee) - (p.MainNum*p.Discount)) + ((p.Tax + p.Charges)*p.MainNum),
                                Discount = p.Discount*p.MainNum,
                                TaxChange = (p.Tax + p.Charges)*p.MainNum
                            }).ToList();
        }

        // if you get back no data -> add a dummy entry
        if (list.Count <= 0)
        {
             list.Add(new SalesInfo { Description = "(no data found)" });
        }
    }
    catch (Exception ex)
    {
        PMessageBox.Show(ex.Message, "Error in Reading  ReturnSalesFactor_Details Data");
    }

    // return the resulting list
    return list;
}