vb.net - 更新数据库时如何用一些值填充空文本框？

Question

我有一个包含 6 个组框和 120 个文本框的表单。在向数据库更新数据期间，我希望空文本框返回值“-NA-”。我尝试了以下代码，但我不断收到错误：

     For i As Integer = 1 To 20
        If GroupBox1.Controls("CollarTB" & i).Text = String.Empty Then
            GroupBox1.Controls("CollarTB" & i).Text = "-NA-"
        End If

        If Me.GroupBox1.Controls("CollarTB" & i).Text = String.Empty Then
            Me.Controls("CollarTB" & i).Text = "-NA-"
        End If

        If Form9.Controls(i).Text = String.Empty Then
            Form9.Controls(i).Text = "-NA-"
        End If

    Next



        If FrntTB1.Text = String.Empty Then FrntTB1.Text = "-NA-"

如何才能做到这一点？请问有什么解决办法吗？

此外，我还有一个包含大约 180 个文本框的组框。我想一次从数据库的一行中填充它们。是否可以？如果是这样，怎么做？

Answer 1

您可以使用从linq中过滤，因为您可以过滤掉，然后根据您的要求简单地将值设置为该值。试试这个代码，groupboxesformgroupboxestextboxestextboxes

Linq 类型 I：

For Each xGroupBox As GroupBox In Me.Controls.OfType(Of GroupBox)()

    For Each xTextBox As TextBox In xGroupBox.Controls.OfType(Of TextBox)()

        If xTextBox.Name.StartsWith("CollarTB") andalso xTextBox.text = string.empty Then
            xTextBox.Text = "-NA-"
        End If

    Next

Next

Linq II 型：

 For Each xGroupBox As GroupBox In Me.Controls.OfType(Of GroupBox)()
     For Each xTextBox As TextBox In From xTxtbx In xGroupBox.Controls.OfType(Of TextBox)() Where xTxtbx.Text.StartsWith("CollarTB") and xTxtbx.text = string.empty
         xTextBox.Text = "-NA-"
     Next
 Next

非 Linq 版本：

For Each xControls As Control In Me.Controls

    If TypeOf xControls Is GroupBox Then

        For Each xControls1 As Control In xControls.Controls

            If TypeOf xControls1 Is TextBox Then

                If xControls1.Name.StartsWith("CollarTB") andalso xControls1.text = string.empty  Then

                    xControls1.Text = "-NA-"

                End If

            End If

        Next

    End If
    Next