Question

寻找一种从ComboBox中填充的100多个值中获取所选字符串值的方法。下面的函数旨在从DB获取预期值并将值返回给ComboBox。

Public Function popuList(Optional dt As DataTable = Nothing)
    Dim daParties As New OleDb.OleDbDataAdapter("SELECT party_ID, party_Name FROM tbl_Parties ORDER BY party_Name;", connKMVTDB)
    Dim dsParties As New DataSet
    Dim dtParties As New DataTable

    daParties.Fill(dsParties, "party_Name")
    dtParties = dsParties.Tables(0)

    Return dtParties
End Function

正如所料，以下事件也可以正常运作。

Private Sub btnPartyLOV_Click(sender As System.Object, e As System.Windows.RoutedEventArgs) Handles btnPartyLOV.Click
    If cmbPartiesList.Visibility = Windows.Visibility.Visible Then
        cmbPartiesList.Visibility = Windows.Visibility.Hidden
    Else
        Dim dtParties As DataTable
        dtParties = popuList()

        cmbPartiesList.ItemsSource = dtParties.DefaultView
        cmbPartiesList.DisplayMemberPath = dtParties.Columns(1).ToString
        cmbPartiesList.SelectedValuePath = dtParties.Columns(0).ToString

        cmbPartiesList.Visibility = Windows.Visibility.Visible
        'cmbPartiesList.SelectedIndex = 0
    End If
End Sub

但是如何将ComboBox中的选定文本值转换为另一个TextBox？在下面试过并坚持......

Private Sub cmbPartiesList_SelectionChanged(sender As Object, e As System.Windows.Controls.SelectionChangedEventArgs) Handles cmbPartiesList.SelectionChanged
    Dim selItem As String = DirectCast(cmbPartiesList.SelectedItem, ComboBoxItem).Content.ToString()

    MsgBox(selItem)
    lblID.Content = cmbPartiesList.SelectedValue
    txtAdd1.Text = cmbPartiesList.DisplayMemberPath
    cmbPartiesList.Visibility = Windows.Visibility.Hidden
End Sub

我反复收到错误......

无法将类型为“System.Data.DataRowView”的对象强制转换为类型 'System.Windows.Controls.ComboBoxItem'

这里搁置了很长时间，任何帮助都将受到高度赞赏和支持。好评。

Answer 1

记住...... ToString() 是你的朋友！

这很简单：

Private Sub cmbPartiesList_SelectionChanged(sender As Object, e As System.Windows.Controls.SelectionChangedEventArgs) Handles cmbPartiesList.SelectionChanged
    Dim selItem As String = cmbPartiesList.SelectedItem.ToString()
    MsgBox(selItem)

    lblID.Content = cmbPartiesList.SelectedValue
    txtAdd1.Text = cmbPartiesList.DisplayMemberPath
    cmbPartiesList.Visibility = Windows.Visibility.Hidden
End Sub

Answer 2

我试过马修，毫无用处。看...

Private Sub cmbPartiesList_SelectionChanged(sender As Object, e As System.Windows.Controls.SelectionChangedEventArgs) Handles cmbPartiesList.SelectionChanged
    Dim drv As DataRowView = cmbPartiesList.SelectedItem
    txtPName.Text = drv.Item(1).ToString()
End Sub

这解决了我的问题，错误，怀疑等。在这里，我创建了一个DataRowView类来存储在此调用期间传递的当前行项。结果被收集为一行并将它们与项目对象分开，这基本上暴露了基础结果。

无论如何，谢谢你的时间。对上述内容的任何建议/更正/修改/改进/批评均受到高度赞赏。

获取ComboBox文本内容并传递给TextBox

2 个答案: