Запретить ввод в текстовое поле определенных символов

Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
 
    '97 - 122 = Ascii codes for simple letters
    '65 - 90  = Ascii codes for capital letters
    '48 - 57  = Ascii codes for numbers
 
    If Asc(e.KeyChar) <> 8 Then
        If Asc(e.KeyChar) < 48 Or Asc(e.KeyChar) > 57 Then
            e.Handled = True
        End If
    End If
 
End Sub

Imports System.Text.RegularExpressions
'...
 
    Private _lastText As String = String.Empty
    Private _lastPos As Integer
    Private _lockEv As Boolean = False
    'Private _pattern As String = "^(?:\d{0,3}|(?:\d{1,3}\.\d{0,3})|(?:\d{1,3}\.\d{1,3}\.\d{0,3}))$"
    Private _pattern As String = "^(?:\d*|(?:\d+\.\d*)|(?:\d+\.\d+\.\d*))$"
 
    Private Sub TextBox1_TextChanged(sender As Object, e As EventArgs) Handles TextBox1.TextChanged
        If _lockEv Then Return
        Dim tb As TextBox = CType(sender, TextBox)
        Dim txt As String = tb.Text
        If Not Regex.IsMatch(txt, _pattern) Then
            _lockEv = True
            tb.Text = _lastText
            _lockEv = False
            tb.SelectionStart = _lastPos
        Else
            _lastText = txt
            _lastPos = tb.SelectionStart
        End If
    End Sub
 
    Private Sub TextBox1_KeyPress(sender As Object, e As KeyPressEventArgs) Handles TextBox1.KeyPress
        If Not (Char.IsControl(e.KeyChar) Or Char.IsDigit(e.KeyChar) Or e.KeyChar = "."c) Then
            e.Handled = True
        End If
    End Sub