sfilename = cfString.AsString() ;
int pos = sfilename.Find('.', true) ;
if ( pos != wxNOT_FOUND && extension != wxT("*") )
{
sfilename = sfilename.Left(pos+1)+extension ;
sfilename = cfString.AsString() ;
int pos = sfilename.Find('.', true) ;
if ( pos != wxNOT_FOUND && extension != wxT("*") )
{
sfilename = sfilename.Left(pos+1)+extension ;