daoview.cpp

c语言编程软件vc6.0中文绿色版_vc6.0官方下载

// This is a part of the Microsoft Foundation Classes C++ library.
// Copyright (C) 1992-1998 Microsoft Corporation
// All rights reserved.
//
// This source code is only intended as a supplement to the
// Microsoft Foundation Classes Reference and related
// electronic documentation provided with the library.
// See these sources for detailed information regarding the
// Microsoft Foundation Classes product.

#include "stdafx.h"

#ifdef AFX_DB_SEG
#pragma code_seg(AFX_DB_SEG)
#endif

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

#define new DEBUG_NEW

/////////////////////////////////////////////////////////////////////////////

IMPLEMENT_DYNAMIC(CDaoRecordView, CFormView)

BEGIN_MESSAGE_MAP(CDaoRecordView, CFormView)
	//{{AFX_MSG_MAP(CDaoRecordView)
		// NOTE - the ClassWizard will add and remove mapping macros here.
	//}}AFX_MSG_MAP
	ON_COMMAND_EX(ID_RECORD_FIRST, OnMove)
	ON_UPDATE_COMMAND_UI(ID_RECORD_FIRST, OnUpdateRecordFirst)
	ON_COMMAND_EX(ID_RECORD_PREV, OnMove)
	ON_UPDATE_COMMAND_UI(ID_RECORD_PREV, OnUpdateRecordPrev)
	ON_COMMAND_EX(ID_RECORD_NEXT, OnMove)
	ON_UPDATE_COMMAND_UI(ID_RECORD_NEXT, OnUpdateRecordNext)
	ON_COMMAND_EX(ID_RECORD_LAST, OnMove)
	ON_UPDATE_COMMAND_UI(ID_RECORD_LAST, OnUpdateRecordLast)
END_MESSAGE_MAP()

CDaoRecordView::CDaoRecordView(LPCTSTR lpszTemplateName)
	: CFormView(lpszTemplateName)
{
	m_nStatus = 0;

	// Setup dummy bookmarks
	m_varBookmarkCurrent = 1L;
	m_varBookmarkFirst = m_varBookmarkLast = 0L;
}

CDaoRecordView::CDaoRecordView(UINT nIDTemplate)
	: CFormView(nIDTemplate)
{
	m_nStatus = 0;

	// Setup dummy bookmarks
	m_varBookmarkCurrent = 1L;
	m_varBookmarkFirst = m_varBookmarkLast = 0L;
}

CDaoRecordView::~CDaoRecordView()
{
}

void CDaoRecordView::OnInitialUpdate()
{
	ASSERT_VALID(this);

	CDaoRecordset* pRecordset = OnGetRecordset();
	// recordset must be allocated already
	ASSERT(pRecordset != NULL);

	if (!pRecordset->IsOpen())
	{
		CWaitCursor wait;
		pRecordset->Open();
	}

	if (!pRecordset->IsEOF())
	{
		// Determine recordset properties for move button enabling
		if (pRecordset->CanBookmark())
		{
			// Get the bookmark of the first record
			m_varBookmarkCurrent = pRecordset->GetBookmark();
			m_varBookmarkFirst = m_varBookmarkCurrent;
		}

		// Enable forward scrolling buttons
		m_nStatus |= AFX_DAOVIEW_SCROLL_NEXT;

		// Enable backward scrolling buttons if possible
		if (pRecordset->CanScroll())
		{
			m_nStatus |= AFX_DAOVIEW_SCROLL_LAST;
			m_nStatus |= AFX_DAOVIEW_SCROLL_BACKWARD;
		}
		else
		{
			m_nStatus &= ~AFX_DAOVIEW_SCROLL_LAST;
			m_nStatus &= ~AFX_DAOVIEW_SCROLL_BACKWARD;
		}
	}
	else
	{
		// Disable scrolling
		m_nStatus &= ~AFX_DAOVIEW_SCROLL_NEXT;
		m_nStatus &= ~AFX_DAOVIEW_SCROLL_LAST;
		m_nStatus &= ~AFX_DAOVIEW_SCROLL_BACKWARD;
	}

	CFormView::OnInitialUpdate();
}

BOOL CDaoRecordView::OnMove(UINT nIDMoveCommand)
{
	ASSERT_VALID(this);

	CDaoRecordset* pSet = OnGetRecordset();
	if (pSet->CanUpdate())
	{
		pSet->Edit();
		if (!UpdateData())
			return TRUE;

		if (pSet->IsFieldDirty(NULL))
			pSet->Update();
		else
			pSet->CancelUpdate();
	}

	BOOL bBookmarkable = pSet->CanBookmark();
	BOOL bScrollable = pSet->CanScroll();

	switch (nIDMoveCommand)
	{
		case ID_RECORD_PREV:
			pSet->MovePrev();

			if (!pSet->IsBOF())
			{
				if (bBookmarkable)
					m_varBookmarkCurrent = pSet->GetBookmark();

				// Enable forward scrolling
				m_nStatus |= AFX_DAOVIEW_SCROLL_NEXT;

				if (bScrollable)
				{
					m_nStatus |= AFX_DAOVIEW_SCROLL_LAST;

					if (IsOnFirstRecord())
						// Disable backward scrolling
						m_nStatus &= ~AFX_DAOVIEW_SCROLL_BACKWARD;
					else
						m_nStatus |= AFX_DAOVIEW_SCROLL_BACKWARD;
				}
				else
				{
					m_nStatus &= ~AFX_DAOVIEW_SCROLL_LAST;
					m_nStatus &= ~AFX_DAOVIEW_SCROLL_BACKWARD;
				}


				break;
			}
			// Fall through to reset to first record

		case ID_RECORD_FIRST:
			pSet->MoveFirst();

			// backward scrolling never allowed after movefirst
			m_nStatus &= ~AFX_DAOVIEW_SCROLL_BACKWARD;

			if (pSet->IsEOF())
			{
				// Empty recordset, disable forward too
				m_nStatus &= ~AFX_DAOVIEW_SCROLL_NEXT;
				m_nStatus &= ~AFX_DAOVIEW_SCROLL_LAST;
			}
			else
			{
				if (bBookmarkable)
				{
					m_varBookmarkCurrent = pSet->GetBookmark();
					m_varBookmarkFirst = m_varBookmarkCurrent;
				}

				// Enable forward scrolling
				m_nStatus |= AFX_DAOVIEW_SCROLL_NEXT;

				if (bScrollable)
					m_nStatus |= AFX_DAOVIEW_SCROLL_LAST;
				else
					m_nStatus &= ~AFX_DAOVIEW_SCROLL_LAST;
			}

			break;

		case ID_RECORD_NEXT:
			pSet->MoveNext();

			if (!pSet->IsEOF())
			{
				if (bBookmarkable)
					m_varBookmarkCurrent = pSet->GetBookmark();

				if (IsOnLastRecord())
				{
					// Disable forward scrolling
					m_nStatus &= ~AFX_DAOVIEW_SCROLL_NEXT;
					m_nStatus &= ~AFX_DAOVIEW_SCROLL_LAST;
				}
				else
				{
					m_nStatus |= AFX_DAOVIEW_SCROLL_NEXT;
					m_nStatus |= AFX_DAOVIEW_SCROLL_LAST;
				}

				if (bScrollable)
					m_nStatus |= AFX_DAOVIEW_SCROLL_BACKWARD;
				else
				{
					m_nStatus &= ~AFX_DAOVIEW_SCROLL_LAST;
					m_nStatus &= ~AFX_DAOVIEW_SCROLL_BACKWARD;
				}

				break;
			}

			// Can't fall through to move last
			if (!bScrollable)
			{
				// At the end of forward only recordset
				m_nStatus &= ~AFX_DAOVIEW_SCROLL_NEXT;
				m_nStatus &= ~AFX_DAOVIEW_SCROLL_LAST;
				m_nStatus &= ~AFX_DAOVIEW_SCROLL_BACKWARD;
				break;
			}

			// Fall through to reset to last record

		case ID_RECORD_LAST:
			pSet->MoveLast();

			// forward scrolling never allowed after movelast
			m_nStatus &= ~AFX_DAOVIEW_SCROLL_NEXT;
			m_nStatus &= ~AFX_DAOVIEW_SCROLL_LAST;

			if (pSet->IsBOF())
			{
				// Empty recordset, disable backward too
				m_nStatus &= ~AFX_DAOVIEW_SCROLL_BACKWARD;
			}
			else
			{
				if (bBookmarkable)
				{
					m_varBookmarkCurrent = pSet->GetBookmark();
					m_varBookmarkLast = m_varBookmarkCurrent;
				}

				// Enable backward scrolling
				if (bBookmarkable)
					m_nStatus |= AFX_DAOVIEW_SCROLL_BACKWARD;
				else
					m_nStatus &= ~AFX_DAOVIEW_SCROLL_BACKWARD;
			}

			break;

		default:
			// Unexpected case value
			ASSERT(FALSE);
	}

	// Show results of move operation
	UpdateData(FALSE);
	return TRUE;
}

BOOL CDaoRecordView::IsOnFirstRecord()
{
	ASSERT_VALID(this);
	return (m_varBookmarkCurrent == m_varBookmarkFirst);
}

BOOL CDaoRecordView::IsOnLastRecord()
{
	ASSERT_VALID(this);
	return (m_varBookmarkCurrent == m_varBookmarkLast);
}

/////////////////////////////////////////////////////////////////////////////
// DDX Cover functions for use with fields of a recordset

/////////////////////////////////////////////////////////////////////////////
// Simple field formatting to text item

BOOL AFXAPI AfxFieldText(CDataExchange* pDX, int nIDC, void* pv,
	CDaoRecordset* pRecordset)
{
	ASSERT_VALID(pRecordset);

	HWND hWndCtrl = pDX->PrepareEditCtrl(nIDC);
	TCHAR szT[2];
	if (pDX->m_bSaveAndValidate)
	{
		::GetWindowText(hWndCtrl, szT, _countof(szT));
		if (szT[0] == '\0')
		{
			// If edit buffer not NULL prior to update, set it dirty
			// to catch case of setting field value from PSEUDO NULL to NULL.
			if (!pRecordset->IsFieldNull(pv))
				pRecordset->SetFieldDirty(pv, TRUE);
			pRecordset->SetFieldNull(pv);
			return TRUE;
		}
		else
		{
			// If edit buffer NULL prior to update, set it dirty
			// to catch case of setting field value to PSEUDO NULL.
			if (pRecordset->IsFieldNull(pv))
				pRecordset->SetFieldDirty(pv, TRUE);
			pRecordset->SetFieldNull(pv, FALSE);
		}
	}
	else
	{
		if (!pRecordset->IsOpen() || pRecordset->IsFieldNull(pv))
		{
			szT[0] = '\0';
			AfxSetWindowText(hWndCtrl, szT);
			return TRUE;
		}
	}
	return FALSE;
}

void AFXAPI DDX_FieldText(CDataExchange* pDX, int nIDC, BOOL& value,
	CDaoRecordset* pRecordset)
{
	if (!AfxFieldText(pDX, nIDC, &value, pRecordset))
		DDX_Text(pDX, nIDC, value);
}

void AFXAPI DDX_FieldText(CDataExchange* pDX, int nIDC, BYTE& value,
	CDaoRecordset* pRecordset)
{
	if (!AfxFieldText(pDX, nIDC, &value, pRecordset))
		DDX_Text(pDX, nIDC, value);
}

void AFXAPI DDX_FieldText(CDataExchange* pDX, int nIDC, short& value,
	CDaoRecordset* pRecordset)
{
	if (!AfxFieldText(pDX, nIDC, &value, pRecordset))
		DDX_Text(pDX, nIDC, value);
}

void AFXAPI DDX_FieldText(CDataExchange* pDX, int nIDC, long& value,
	CDaoRecordset* pRecordset)
{
	if (!AfxFieldText(pDX, nIDC, &value, pRecordset))
		DDX_Text(pDX, nIDC, value);
}

void AFXAPI DDX_FieldText(CDataExchange* pDX, int nIDC, DWORD& value,
	CDaoRecordset* pRecordset)
{
	if (!AfxFieldText(pDX, nIDC, &value, pRecordset))
		DDX_Text(pDX, nIDC, value);
}

void AFXAPI DDX_FieldText(CDataExchange* pDX, int nIDC, COleCurrency& value,
	CDaoRecordset* pRecordset)
{
	if (!AfxFieldText(pDX, nIDC, &value, pRecordset))
		DDX_Text(pDX, nIDC, value);
}

void AFXAPI DDX_FieldText(CDataExchange* pDX, int nIDC, float& value,