Question

我想创建一个程序，通过单击按钮添加6个TextBox控件，然后在标签的文本框中显示6个数字的总和。

我编写了添加文本框的代码，但我的总和有问题。如何获取所有文本框值？

Public Class Form1
    Dim txtn As Integer = 1
    Dim sum As Integer


    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        AddNewTextBox()
    End Sub
    Public Function AddNewTextBox() As TextBox 
        Dim txt As New TextBox()
        Controls.Add(txt)
        txt.Top = txtn * 25 
        txt.Left = 200           
        If txtn < 6 Then
            txtn = txtn + 1       
            Return txt
        Else
            MsgBox("sorry you reached the max number of text boxes")
        End If
    End Function

    Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click
        Label1.Text =       'problem???
    End Sub

End Class

Answer 1

在此之前，请确保验证Texbox输入仅为数字

Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click
    Dim i As Integer = 0
    For Each T As Textbox In Me.Controls.OfType(Of TextBox)()
        Try
            i = i + Val(t.text)
        Catch ex As Exception

        End Try

    Next
    Label1.Text = i
End Sub

循环更新......

Answer 2

您需要获得对动态创建的文本框的引用。你可以在创建它们时将它们添加到列表中，然后在总结时访问它们。

Public Class Form1
    Dim txtn As Integer = 1
    Dim sum As Integer

    Private _textboxesToSum As New List(Of TextBox)

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        AddNewTextBox()
    End Sub

    Public Function AddNewTextBox() As TextBox
        Dim txt As New TextBox()
        Controls.Add(txt)
        _textboxesToSum.Add(txt)
        txt.Top = txtn * 25
        txt.Left = 200
        If txtn < 6 Then
            txtn = txtn + 1
            Return txt
        Else
            MsgBox("sorry you reached the max number of text boxes")
        End If
    End Function

    Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click
        Label1.Text = _textboxesToSum.Select(Of Integer)(Function(t) If(IsNumeric(t.Text), t.Text(), 0)).Sum()
    End Sub

End Class

您也可以通过遍历表单上的所有文本框来执行此操作，但您可能还有其他一些文本框，用于其他目的。

控制动态文本框

2 个答案: