数据直接绑定到商店查询

Question

我正在尝试将金额分组并加载到vb.net(asp.net)的下拉框中

但是我收到以下错误:

不支持直接绑定到商店查询(DbSet,DbQuery,DbSqlQuery,DbRawSqlQuery)的数据.而是使用数据填充DbSet,例如通过在DbSet上调用Load,然后绑定到本地数据.对于WPF绑定到DbSet.Local.对于WinForms绑定到DbSet.Local.ToBindingList().对于ASP.NET WebForms,您可以绑定到查询上调用ToList()的结果或使用模型绑定,有关详细信息,请参阅

我的代码:

'Load Amounts
Dim SourceAmounts = (From p In db.PayoutAdjustments
                     Order By p.Amount
                     Where p.PayoutId = PayoutId
                     Group p By Key = p.Amount Into Group
                     Select Amount = Group)

cmbAmount.DataSource = SourceAmounts
cmbAmount.DataTextField = "Amount"
cmbAmount.DataValueField = "Amount"
cmbAmount.DataBind()
cmbAmount.Items.Insert(0, New ListItem("Select Amount", 0))

Answer 1

您需要在数据绑定之前执行查询.使用ToList()将强制执行查询.

cmbAmount.DataSource = SourceAmounts.ToList()