Missing IsFirstRecord() & IsLastRecord()..

Mihir Dalal -- m_dalal@ECE.concordia.CA
Tuesday, February 25, 1997


                  Environment: MSVC 1.52, Windows 95

Hi,

I am developing an SDI based database enabled windows application on the 
above mentioned platform.

While writing my CMyRecordView class handlers, I need to use the 
IsFirstRecord() & IsLastRecord() member functions frequently. It turns 
out that these functions although documented in Visual C++ 1.52 are not 
implemented in the source code. 

Any suggestions to rectify this or any other alternate way around to 
resolve this problem ??

Mihir. 

 _________________________________________________________________________
     Mihir Dalal , M.Engg. (Electrical) Student
              Department of Electrical and Computer Engineering
                   Concordia University, Montreal, Canada
                http://www.ECE.Concordia.CA/~m_dalal/addr.html

---

Ray Barley -- barley@rdaconsultants.com
Thursday, February 27, 1997

[Mini-digest: 3 responses]

To find out if you're on the first or last record, call CRecordset
GetStatus() like this:

Assuming rs is a CRecordset,

CRecordsetStatus s;
rs.GetStatus(s);
if(s.m_lCurrentRecord == 0)	// it's zero-based
{
  // you are on the first record
}

// To see if you're on the last record is a little more complicated
if(s.m_bRecordCountFinal)        // mean's you hit EOF at some point
{
    long lCount = rs.GetRecordCount();    // how many records in
recordset
    if(lCount == (s.m_lCurrentRecord + 1))
        // you are on the last record.
}

The last record test won't work if you call CRecordset MoveLast().  It
says so in CRecordset GetRecordCount().  If it's really important to
know whether you are on the last record, don't call CRecordset
MoveLast(); do some sort of loop where you keep calling MoveNext() until
you IsEOF() is TRUE.  Check the manual on GetStatus().  There are some
other conditions you might need to be aware of.

>----------
>From: 	Mihir Dalal[SMTP:m_dalal@ECE.concordia.CA]
>Sent: 	Tuesday, February 25, 1997 12:46 PM
>To: 	mfc-l@netcom.com
>Subject: 	Missing IsFirstRecord() & IsLastRecord().. 
>
>
>                  Environment: MSVC 1.52, Windows 95
>
>Hi,
>
>I am developing an SDI based database enabled windows application on the 
>above mentioned platform.
>
>While writing my CMyRecordView class handlers, I need to use the 
>IsFirstRecord() & IsLastRecord() member functions frequently. It turns 
>out that these functions although documented in Visual C++ 1.52 are not 
>implemented in the source code. 
>
>Any suggestions to rectify this or any other alternate way around to 
>resolve this problem ??
>
>Mihir. 
>
> _________________________________________________________________________
>     Mihir Dalal , M.Engg. (Electrical) Student
>              Department of Electrical and Computer Engineering
>                   Concordia University, Montreal, Canada
>                http://www.ECE.Concordia.CA/~m_dalal/addr.html
>
>
>
>
-----From: jeremy@omsys.com (Jeremy H. Griffith)

On Tue, 25 Feb 1997 12:46:44 -0500 (EST), Mihir Dalal 
wrote:
>                  Environment: MSVC 1.52, Windows 95
>
>While writing my CMyRecordView class handlers, I need to use the 
>IsFirstRecord() & IsLastRecord() member functions frequently. It turns 
>out that these functions although documented in Visual C++ 1.52 are not 
>implemented in the source code. 

Try IsOnFirstRecord() and IsOnLastRecord(), which are present in DBVIEW.CPP
in the MFC source for 1.52c, and are listed as public in AFXDB.H.

This appears to be a doc error in MFC.HLP (and possibly the print docs).

--Jeremy
-----From: Shane Triem 


Write your own functions in a base class for your record view.

BOOL CMyRecordViewBase::IsFirstRecord()
{
 BOOL bReturnValue = FALSE;
 if (!IsBOF())
 {
  // Move back one record, check for BOF.
  // If BOF, then you were on the first record.
  // Make sure to move back to original record
  // before returning.
  MovePrev();
  if (IsBOF())
  {
   bReturnValue = TRUE;
  }
  MoveNext();
 }
 return bReturnValue;
}

BOOL CMyRecordViewBase::IsLastRecord()
{
 BOOL bReturnValue = FALSE;
 if (!IsEOF())
 {
  // Move forward one record, check for EOF.
  // If EOF, then you were on the last record.
  // Make sure to move back to original record
  // before returning.
  MoveNext();
  if (IsEOF())
  {
   bReturnValue = TRUE;
  }
  MovePrev();
 }
 return bReturnValue;
}

 ----------
From:  Mihir Dalal
Sent:  Thursday, February 27, 1997 5:55 AM
To:  SHANE; 'MFC-L@SMTP '
Subject:  Missing IsFirstRecord() & IsLastRecord()

Original Subject:
Missing IsFirstRecord() & IsLastRecord()..


                  Environment: MSVC 1.52, Windows 95

Hi,

I am developing an SDI based database enabled windows application on the
above mentioned platform.

While writing my CMyRecordView class handlers, I need to use the
IsFirstRecord() & IsLastRecord() member functions frequently. It turns
out that these functions although documented in Visual C++ 1.52 are not
implemented in the source code.

Any suggestions to rectify this or any other alternate way around to
resolve this problem ??

Mihir.

 _________________________________________________________________________  

     Mihir Dalal , M.Engg. (Electrical) Student
              Department of Electrical and Computer Engineering
                   Concordia University, Montreal, Canada
                http://www.ECE.Concordia.CA/~m_dalal/addr.html

---

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