如何将SQL位字段绑定到“真/假”组合框或列表框?

您可能需要创建一个值转换器(实现 IValueConverter 接口)可以将位字段的值转换为布尔值。问题的一部分是,开箱即用,那就是如何将空值表示为布尔状态?这通常取决于业务流程或规则。

正如对遇到此问题的其他人(不必执行XAML操作)的建议一样,我使用LINQ(VB 2008)执行了以下操作:

Private Sub BindMyCombo()
    Dim yesNo As String() = {"No", "Yes"}   'Or false, true or nay, yay -whatever

    Dim bits = From bit In yesNo _
               Select New With { _
                   .BitVal = Cbool(Array.IndexOf(yesNo, bit)), _
                   .BitText = bit _
               }

    With Me.myBitComboBox
        'Clear anything in the combo first if necessary...
        .DataSource = Nothing
        .Items.Clear()
        'New binding in case there are more "bits" to be used elsewhere in your form
        .BindingContext = New BindingContext
        .DataSource = bits.ToList
        .DisplayMember = "BitText"
        .ValueMember = "BitVal"
    End With

End Sub

在那之后,只需对数据集进行绑定。执行此操作时,请指定当位值为空时,将Combos SelectedValue设置为空或不为空,例如…

With Me.myBitComboBox
    .DataBindings.Clear()
    .DataBindings.Add(New Binding("SelectedValue", myDataSetName, "myBitFieldName", _
                      True, DataSourceUpdateMode.OnPropertyChanged, Nothing))
    .SelectedValue = IIf(mdDataSetName.myBitFieldName.ToString = "", "", _
                         myDataSetName.myBitFieldName)
End With

我希望这能帮助其他遇到这个问题的人(像我一样)。