dbview.cpp

vc6.0完整版

// 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

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

BEGIN_MESSAGE_MAP(CRecordView, CFormView)
	//{{AFX_MSG_MAP(CRecordView)
		// 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()


CRecordView::CRecordView(LPCTSTR lpszTemplateName)
	: CFormView(lpszTemplateName)
{
}

CRecordView::CRecordView(UINT nIDTemplate)
	: CFormView(nIDTemplate)
{
}

CRecordView::~CRecordView()
{
}

void CRecordView::OnInitialUpdate()
{
	CRecordset* pRecordset = OnGetRecordset();
	// recordset must be allocated already
	ASSERT(pRecordset != NULL);

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

	CFormView::OnInitialUpdate();
}

BOOL CRecordView::IsOnFirstRecord()
{
	ASSERT_VALID(this);
	CRecordsetStatus status;
	OnGetRecordset()->GetStatus(status);
	return status.m_lCurrentRecord == 0;
}

BOOL CRecordView::IsOnLastRecord()
{
	ASSERT_VALID(this);
	CRecordset* pRecordset = OnGetRecordset();
	CRecordsetStatus status;
	pRecordset->GetStatus(status);
	if (!status.m_bRecordCountFinal)
		return FALSE;
	return ((status.m_lCurrentRecord+1 == pRecordset->GetRecordCount()));
}

BOOL CRecordView::OnMove(UINT nIDMoveCommand)
{
	CRecordset* pSet = OnGetRecordset();
	if (pSet->CanUpdate() && !pSet->IsDeleted())
	{
		pSet->Edit();
		if (!UpdateData())
			return TRUE;

		pSet->Update();
	}

	switch (nIDMoveCommand)
	{
		case ID_RECORD_PREV:
			pSet->MovePrev();
			if (!pSet->IsBOF())
				break;

		case ID_RECORD_FIRST:
			pSet->MoveFirst();
			break;

		case ID_RECORD_NEXT:
			pSet->MoveNext();
			if (!pSet->IsEOF())
				break;
			if (!pSet->CanScroll())
			{
				// clear out screen since we're sitting on EOF
				pSet->SetFieldNull(NULL);
				break;
			}

		case ID_RECORD_LAST:
			pSet->MoveLast();
			break;

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

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

void CRecordView::OnUpdateRecordFirst(CCmdUI* pCmdUI)
{
	CRecordset* prs = OnGetRecordset();

	// enable if opened, can scroll backwards,
	pCmdUI->Enable(prs->IsOpen() && prs->CanScroll() &&
		// >= 1 records present and not already on first record
		!(prs->IsEOF() && prs->IsBOF()) && !IsOnFirstRecord());
}

void CRecordView::OnUpdateRecordPrev(CCmdUI* pCmdUI)
{
	CRecordView::OnUpdateRecordFirst(pCmdUI);
}

void CRecordView::OnUpdateRecordNext(CCmdUI* pCmdUI)
{
	CRecordset* prs = OnGetRecordset();

	// enable if opened and >= 1 records present
	pCmdUI->Enable(prs->IsOpen() && !(prs->IsEOF() && prs->IsBOF())
		// and not already on last record
		&& !IsOnLastRecord());
}

void CRecordView::OnUpdateRecordLast(CCmdUI* pCmdUI)
{
	CRecordset* prs = OnGetRecordset();

	// enable if opened, can scroll,
	pCmdUI->Enable(prs->IsOpen() && prs->CanScroll() &&
		// >= 1 records present and not already on last record
		!(prs->IsEOF() && prs->IsBOF()) && !IsOnLastRecord());
}



/////////////////////////////////////////////////////////////////////////////
// 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,
	CRecordset* 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 (pRecordset->IsFieldNullable(pv))
			{
				pRecordset->SetFieldNull(pv);
				return TRUE;
			}
		}
		else
			pRecordset->SetFieldNull(pv, FALSE);
	}
	else
	{
		if (!pRecordset->IsOpen() || pRecordset->IsFieldNull(pv))
		{
			szT[0] = '\0';
			AfxSetWindowText(hWndCtrl, szT);
			return TRUE;
		}
		else if (pRecordset->IsDeleted())
		{
			CString strDeleted(MAKEINTRESOURCE(AFX_IDS_DELETED));
			AfxSetWindowText(hWndCtrl, strDeleted);
			return TRUE;
		}
	}
	return FALSE;
}

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

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

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

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

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

void AFXAPI DDX_FieldText(CDataExchange* pDX, int nIDC, CString& value,
	CRecordset* pRecordset)
{
	ASSERT_VALID(pRecordset);
	HWND hWndCtrl = pDX->PrepareEditCtrl(nIDC);
	if (pDX->m_bSaveAndValidate)
	{
		// check if length is too long (this is complicated by Windows NT/J)
		int nLen = ::GetWindowTextLength(hWndCtrl);
		if (nLen > value.GetAllocLength())
		{
			if (!_afxDBCS)
				AfxFailMaxChars(pDX, value.GetAllocLength());
			CString strTemp;
			::GetWindowText(hWndCtrl, strTemp.GetBuffer(nLen), nLen+1);
			strTemp.ReleaseBuffer();
			nLen = strTemp.GetLength();
			if (nLen > value.GetAllocLength())
				AfxFailMaxChars(pDX, value.GetAllocLength());
		}
		// get known length
		::GetWindowText(hWndCtrl, value.GetBuffer(0), nLen+1);
		value.ReleaseBuffer();
		if (nLen == 0)
		{
			if (pRecordset->IsFieldNullable(&value))
				pRecordset->SetFieldNull(&value, TRUE);
		}
		else
		{
			pRecordset->SetFieldNull(&value, FALSE);
		}
	}
	else if (pRecordset->IsDeleted())
	{
		CString strDeleted(MAKEINTRESOURCE(AFX_IDS_DELETED));
		AfxSetWindowText(hWndCtrl, strDeleted);
	}
	else
	{
		AfxSetWindowText(hWndCtrl, value);
	}
}

void AFXAPI DDX_FieldText(CDataExchange* pDX, int nIDC, LPTSTR pstrValue,
	int nMaxLength, CRecordset* pRecordset)
{
	ASSERT_VALID(pRecordset);
	HWND hWndCtrl = pDX->PrepareEditCtrl(nIDC);
	if (pDX->m_bSaveAndValidate)
	{
		int nLen = ::GetWindowText(hWndCtrl, pstrValue, nMaxLength);

		if (nLen == 0)
		{
			if (pRecordset->IsFieldNullable(pstrValue))
				pRecordset->SetFieldNull(pstrValue, TRUE);
		}
		else
			pRecordset->SetFieldNull(pstrValue, FALSE);
	}
	else if (pRecordset->IsDeleted())
	{
		CString strDeleted(MAKEINTRESOURCE(AFX_IDS_DELETED));
		AfxSetWindowText(hWndCtrl, strDeleted);
	}
	else
		AfxSetWindowText(hWndCtrl, pstrValue);
}

void AFXAPI DDX_FieldLBString(CDataExchange* pDX, int nIDC, CString& value,
	CRecordset* pRecordset)
{
	ASSERT_VALID(pRecordset);

	HWND hWndCtrl = pDX->PrepareCtrl(nIDC);
	if (pDX->m_bSaveAndValidate)