Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
    System.EventArgs) Handles Button1.Click
        Dim Zeile As String
        Zeile = TextBox1.Text()
        If Zeile.IndexOf("ft") Or Zeile.IndexOf("in") <> -1 Then
            MsgBox("Inch oder Feet")
        Else
            MsgBox("Meter")
        End If
    End Sub