我想從實體框架的數據庫中獲取數據,並在listview中顯示,我想在實體框架中實現連接,但它返回null!我在我的數據庫中有數據。加入對我不起作用
我的代碼:
using (var context = new MyEntities())
{
IEnumerable<Core_Permissions> MyList = (from p in context.Core_Permissions
from rp in context.Core_RolePermissions
where p.PermissionID == rp.PermissionID
where rp.RoleID == roleid
select p).ToList();
lvGranted.DataSource = MyList;
lvGranted.DataBind();
}
或:
(from p in context.Core_Permissions
join rp in context.Core_RolePermissions
on p.PermissionID equals rp.PermissionID select rp).ToList();
HTML:
<asp:ListView ID="lvGranted" runat="server" >
<LayoutTemplate>
<ul id="sortable1" class="connectedSortable" style="min-height: 200px;width: 300px;border: 1px solid black;">
<li id="itemPlaceholder" runat="server"></li>
</ul>
</LayoutTemplate>
<ItemTemplate>
<li id="itemPlaceholder" runat="server" >
<label id='<%#Eval("PermissionID") %>'><%#Eval("RoleID") %></label>
</li>
</ItemTemplate>
</asp:ListView>
在另一方面我喬恩查詢返回空!但我的數據庫中有數據。
使用探查並查看生成的查詢或張貼在這裏生成的查詢。 – Win
對不起,但我應該如何使用Profiler? –
EXEC sp_executesql的N'SELECT [Extent1] [PermissionID] AS [PermissionID], [Extent1] [PermissionGroupID] AS [PermissionGroupID], [Extent1] [PermissionName] AS [PermissionName], [Extent1]。 [PermissionTitle] AS [PermissionTitle] FROM [dbo]。[Core_Permissions] AS [Extent1] INNER JOIN [dbo]。[Core_RolePermissions] AS [Extent2] ON [Extent1]。[PermissionID] = [Extent2]。[PermissionID] WHERE [Extent2]。[RoleID] = @ p__linq__14',N'@ p__linq__14 int',@ p__linq__14 = 1 –