C / C++ / MFC

typedef enum calibDataType_e
{
	CDT_UNKNOWN_E = 0,
	CDT_REGISTER_E,
	CDT_END_E		/*Keep as last*/
} calibDataType_t;

//the class
class CCalibEntry : public CDialog
{
public:
   CString csLabel;
   CString csValue;
   float fValue;
   enum { IDD = IDD_VALUEENTRY };
public:
   CCalibEntry(CString csLabel, CWnd* pParent = NULL);
   CCalibEntry(CString csLabel, calibDataType_t pt = CDT_UNKNOWN_E, CWnd* pParent = NULL);
protected:
   bool   IsValidEntry();
   bool   ValidateRegisterEntry();
   virtual BOOL OnInitDialog();
   virtual void OnOK();
   afx_msg void OnDestroy( );
   DECLARE_MESSAGE_MAP()
private:
   int dataType;
};

//The constructors. Note the differing constructor signatures
CCalibEntry::CCalibEntry (CString csLabel, CWnd *pParent) : CDialog (IDD, pParent), dataType(CDT_UNKNOWN_E)
{
    this->csLabel = csLabel;
}

CCalibEntry::CCalibEntry (CString csLabel, calibDataType_t dt, CWnd *pParent) : CDialog (IDD, pParent)
{
    this->csLabel = csLabel;
   dataType = dt;

   if( dataType == CDT_REGISTER_E )
   {
      //provide a hint to the user
      csValue = _T("0.0.0");
   }
}