hola que tal bueno mira esto es lo que se me ocurrió si puedes mejorarlo bacan
Public Class Form1
Dim I As Byte
Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
If Asc(e.KeyChar) = 44 Then
If I = 1 Then
e.Handled = True
Exit Sub
End If
I = 1
Exit Sub
End If
If Asc(e.KeyChar) = 8 Then
Exit Sub
End If
If Asc(e.KeyChar) < 48 Or Asc(e.KeyChar) > 57 Then
e.Handled = True
End If
End Sub
Private Sub TextBox1_TextChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles TextBox1.TextChanged
If Me.TextBox1.Text.IndexOf(",") = -1 Then
I = 0
End If
End Sub
End Class
bueno espero que te sirva, nos vemos
