问VB如何选择所有类型的控件并将文本设置为Nothing

EN

  Imports System.Media
Public Class comboForm

    Dim score As Integer = 0
    Dim winsound As New SoundPlayer(My.Resources.winsound_wav)



    ' 1 7 8 8 4 7 1 5 5



    Private Sub btn1_Click(sender As Object, e As EventArgs) Handles btn1.Click
        If score = 0 Then
            score += 1
            lblStage1.Text = "1"
        ElseIf score = 7 Then
            score += 1
            lblStage7.Text = "7"
        Else
            score = 0
            For Each lbl In tlpMain.Controls.OfType(Of Label)()
                lbl.Text = Nothing
            Next


        End If

    End Sub
End Class