Webアプリで動的に生成したテキストボックスの値を取得する方法

Option Strict On

Public Class TextBoxCollection
    Inherits System.Collections.ArrayList

    Public Shadows Function Add(ByVal value As TextBox) As Integer
        Return MyBase.Add(value)
    End Function

    Public Shadows Default Property Item(ByVal index As Integer) As TextBox
        Get
            Return DirectCast(MyBase.Item(index), TextBox)
        End Get

        Set
            MyBase.Item(index) = Value
        End Set
    End Property

End Class

Option Strict On

Public Class WebForm1
    Inherits System.Web.UI.Page

[ Web フォーム デザイナで生成されたコード ]

    Private MyTextBoxes As TextBoxCollection

    Private Sub Page_Load(...) Handles MyBase.Load
        Me.MyTextBoxes = New TextBoxCollection()

        Dim hTextBox1 As New TextBox()
        hTextBox1.ID = "TextBox1"
        hTextBox1.Style("margin-top")  = "25px"
        hTextBox1.Style("margin-left") = "100px"

        Dim hForm As Control = Me.FindControl("Form1")
        hForm.Controls.Add(hTextBox1)
        Me.MyTextBoxes.Add(hTextBox1)

        Dim hTextBox2 As New TextBox()
        hTextBox2.ID = "TextBox2"
        hTextBox2.Style("margin-top")  = "25px"
        hTextBox2.Style("margin-left") = "200px"

        hForm.Controls.Add(hTextBox2)
        Me.MyTextBoxes.Add(hTextBox2)
    End Sub

    Private Sub Button1_Click(...) Handles Button1.Click
        Dim sPrompt As String = "TextBox の数 : " & Me.MyTextBoxes.Count.ToString() & Environment.NewLine

        sPrompt &= "各 TextBox の値 : " & Environment.NewLine

        For Each hTextBox As TextBox In Me.MyTextBoxes
            sPrompt &= hTextBox.ID & " : " & hTextBox.Text & Environment.NewLine
        Next hTextBox

        Me.Button1.Text = sPrompt
    End Sub

End Class