Try something like
VB Code:
  1. If KeyAscii = 46 Then
  2.    If InStr(1, Text1.Text, ".") = 0 Then 'there is no decimal point
  3.       'do whatever you need to do if there is no decimal point  
  4.    Else
  5.       'there is a decimal point, so whatever is appopriate here
  6.    End If
  7. End If