如何在vb.net的tabcontrol中删除动态创建的文本框？

Question

我创建了一个程序，根据从组合框中选择的数字动态创建文本框。问题是当我将数字从大数字改为小数字时，文本框保持相同的ex（10然后是3）。 see this image  我尝试输入一个代码来删除* for循环之前的文本框但是它不起作用。

Private Sub ComboBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedIndexChanged
        num = ComboBox1.Text
        Dim tp As TabPage = tabControl1.TabPages(0)
        *For i = 1 To num
            Dim TB As New TextBox
            TB.Size = New System.Drawing.Size(60, 20)
            TB.Font = New System.Drawing.Font("arial", 20)
            TB.Location = New Point(10, i * 40)
            TB.Name = "tbt" & i
            Select Case i
                Case 1 To 5
                    TB.Location = New Point(10, i * 45)
                Case 6 To 10
                    Dim i2 As Integer = i - 5
                    TB.Location = New Point(80, i2 * 45)
            End Select
            tp.Controls.Add(TB)
        Next
    End Sub

注意：我在没有tabcontrol的情况下尝试了这种方法，它运行得很好。

     Private Sub ComboBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedIndexChanged
            _Textboxes.ForEach(New Action(Of TextBox)(AddressOf Controls.Remove))
            _Textboxes.Clear()
            num = ComboBox1.Text
            ...
                End Select
                Controls.Add(TB)
                _Textboxes.Add(TB)
            Next