我正在努力与Linq到实体。我是EF5和Linq的新手。我在VB.NET编程。我一直在使用表适配器,它将数据集作为DAL返回到一个BLL,然后链接到ObjectDataSource。现在我从VS2005 ASP升级到VS2012。. NET 2.0到ASO。. NET 4.0使用EF5,我已经将EF5设置为DAL,我正试图重写BAL以使用实体链接到ObjectDataSource。我可以做一些复杂的查询多个表使用导航我设置外键,但我不明白如何获得返回类型与ObjectDataSource工作,它期望一个数据集。
ContentQ = From ct In DAL.Contents, cd In ct.ContentDuplicateTypes, ce In ct.ContentEditors _
Where ct.ContentId = Contentid And cd.ShowOnWeb = ShowOnWeb And cd.Hide = Hide And ce.UserId = UserId And ct.websiteId = websiteid Select ct, cd, ce
用于返回单个表ContentQ= From ct in DAL。内容选择ct
为什么下面会这样?为什么我必须填充这个类,以便使用include方法将其放入ObjectDataSource中,并使用1对多的2个表?
<System.ComponentModel.DataObjectMethodAttribute(ComponentModel.DataObjectMethodType.Select, True)> _
Public Function GetContentFiles() As ContentData
Dim objContentData As New ContentData
Using _SBEF As New SBEF5
Dim objContentDuplicateType = From d In _SBEF.ContentDuplicateTypes.Include("Content") Select d
For Each objQuery In objContentDuplicateType.ToList
With objContentData
'Content
.Description = objQuery.Content.Description
.FileName = objQuery.Content.FileName
.Draft_Path = objQuery.Content.Draft_Path
.Live_Path = objQuery.Content.Live_Path
.HeaderTitle = objQuery.Content.HeaderTitle
'ContentDuplicateType
.ContentId = objQuery.ContentId
.DisplayHeader = objQuery.DisplayHeader
.OrderNumber = objQuery.OrderNumber
.ShowOnWeb = objQuery.ShowOnWeb
.Hide = objQuery.Hide
.DateCreated = objQuery.DateCreated
.ContentTypeID = objQuery.ContentTypeId
End With
Next
GetContentFiles = objContentData
End Using
End Function
为什么不使用EntityDataSource?