datalink.cpp

数据访问的定义类

	SqlString_Insert(joined_table, nStart2, strItem);
	SqlString_Stuff(*this, nStart1, nCount1, joined_table);
	return nIndex;
}

void CSqlString::DeleteJoinedTable(int nIndex)
{
	int nStart1, nCount1;
	SqlString_JoinedTable(*this, nStart1, nCount1);
	CString joined_table = Mid(nStart1, nCount1);

	int nStart2, nCount2;
	if (!SqlString_JoinedTableItem(joined_table, nIndex, nStart2, nCount2))
		return;

	joined_table.Delete(nStart2, nCount2 + 1);
	if (nStart2 == joined_table.GetLength())
		joined_table.Delete(nStart2 - 1, 1);

	SqlString_Stuff(*this, nStart1, nCount1, joined_table);
}

// join_type and search_condition
CString CSqlString::GetJoinType(int nIndex)
{
	CString joined_table = GetJoinedTable();

	int nStart1, nCount1;
	SqlString_JoinedTableItem(joined_table, nIndex, nStart1, nCount1);
	CString table_item = joined_table.Mid(nStart1, nCount1);

	int nStart2, nCount2;
	SqlString_JoinType(table_item, nStart2, nCount2);
	return table_item.Mid(nStart2, nCount2);
}

CString CSqlString::GetJoinType(LPCTSTR lpszTableAlias)
{
	CString joined_table = GetJoinedTable();

	int nStart1, nCount1;
	CString strTableAlias(lpszTableAlias);
	SqlString_Alias(strTableAlias);
	int nIndex = SqlString_JoinedTableIndex(joined_table, strTableAlias);
	SqlString_JoinedTableItem(joined_table, nIndex, nStart1, nCount1);
	CString table_item = joined_table.Mid(nStart1, nCount1);

	int nStart2, nCount2;
	SqlString_JoinType(table_item, nStart2, nCount2);
	return table_item.Mid(nStart2, nCount2);
}

CString CSqlString::GetJoinCondition(int nIndex)
{
	CString joined_table = GetJoinedTable();

	int nStart1, nCount1;
	SqlString_JoinedTableItem(joined_table, nIndex, nStart1, nCount1);
	CString table_item = joined_table.Mid(nStart1, nCount1);

	int nStart2, nCount2;
	SqlString_JoinCondition(table_item, nStart2, nCount2);
	return table_item.Mid(nStart2, nCount2);
}

CString CSqlString::GetJoinCondition(LPCTSTR lpszTableAlias)
{
	CString joined_table = GetJoinedTable();

	int nStart1, nCount1;
	CString strTableAlias(lpszTableAlias);
	SqlString_Alias(strTableAlias);
	int nIndex = SqlString_JoinedTableIndex(joined_table, strTableAlias);
	SqlString_JoinedTableItem(joined_table, nIndex, nStart1, nCount1);
	CString table_item = joined_table.Mid(nStart1, nCount1);

	int nStart2, nCount2;
	SqlString_JoinCondition(table_item, nStart2, nCount2);
	return table_item.Mid(nStart2, nCount2);
}

void CSqlString::SetJoinType(int nIndex, LPCTSTR lpszType)
{
	int nStart1, nCount1;
	SqlString_JoinedTable(*this, nStart1, nCount1);
	CString joined_table = Mid(nStart1, nCount1);

	int nStart2, nCount2;
	if (!SqlString_JoinedTableItem(joined_table, nIndex, nStart2, nCount2))
		return;
	CString table_item = joined_table.Mid(nStart2, nCount2);

	int nStart3, nCount3;
	SqlString_JoinType(table_item, nStart3, nCount3);
	SqlString_Stuff(table_item, nStart3, nCount3, lpszType);
	SqlString_Stuff(joined_table, nStart2, nCount2, table_item);
	SqlString_Stuff(*this, nStart1, nCount1, joined_table);
}

void CSqlString::SetJoinType(LPCTSTR lpszTableAlias, LPCTSTR lpszType)
{
	int nStart1, nCount1;
	SqlString_JoinedTable(*this, nStart1, nCount1);
	CString joined_table = Mid(nStart1, nCount1);

	int nStart2, nCount2;
	CString strTableAlias(lpszTableAlias);
	SqlString_Alias(strTableAlias);
	int nIndex = SqlString_JoinedTableIndex(joined_table, strTableAlias);
	if (!SqlString_JoinedTableItem(joined_table, nIndex, nStart2, nCount2))
		return;
	CString table_item = joined_table.Mid(nStart2, nCount2);

	int nStart3, nCount3;
	SqlString_JoinType(table_item, nStart3, nCount3);
	SqlString_Stuff(table_item, nStart3, nCount3, lpszType);
	SqlString_Stuff(joined_table, nStart2, nCount2, table_item);
	SqlString_Stuff(*this, nStart1, nCount1, joined_table);
}

void CSqlString::SetJoinCondition(int nIndex, LPCTSTR lpszCondition)
{
	int nStart1, nCount1;
	SqlString_JoinedTable(*this, nStart1, nCount1);
	CString joined_table = Mid(nStart1, nCount1);

	int nStart2, nCount2;
	if (!SqlString_JoinedTableItem(joined_table, nIndex, nStart2, nCount2))
		return;
	CString table_item = joined_table.Mid(nStart2, nCount2);

	int nStart3, nCount3;
	SqlString_JoinCondition(table_item, nStart3, nCount3);
	SqlString_Stuff(table_item, nStart3, nCount3, lpszCondition);
	SqlString_Stuff(joined_table, nStart2, nCount2, table_item);
	SqlString_Stuff(*this, nStart1, nCount1, joined_table);
}

void CSqlString::SetJoinCondition(LPCTSTR lpszTableAlias, LPCTSTR lpszCondition)
{
	int nStart1, nCount1;
	SqlString_JoinedTable(*this, nStart1, nCount1);
	CString joined_table = Mid(nStart1, nCount1);

	int nStart2, nCount2;
	CString strTableAlias(lpszTableAlias);
	SqlString_Alias(strTableAlias);
	int nIndex = SqlString_JoinedTableIndex(joined_table, strTableAlias);
	if (!SqlString_JoinedTableItem(joined_table, nIndex, nStart2, nCount2))
		return;
	CString table_item = joined_table.Mid(nStart2, nCount2);

	int nStart3, nCount3;
	SqlString_JoinCondition(table_item, nStart3, nCount3);
	SqlString_Stuff(table_item, nStart3, nCount3, lpszCondition);
	SqlString_Stuff(joined_table, nStart2, nCount2, table_item);
	SqlString_Stuff(*this, nStart1, nCount1, joined_table);
}

// search_condition, group_by_expression and sort_expression
CString CSqlString::GetSearchCondition(BOOL bCompute /* = FALSE */)
{
	int nIndex, nCount;
	SqlString_SearchCondition(*this, nIndex, nCount, bCompute);
	return Mid(nIndex, nCount);
}

CString CSqlString::GetGroupByExpression()
{
	int nIndex, nCount;
	SqlString_GroupByExpression(*this, nIndex, nCount);
	return Mid(nIndex, nCount);
}

CString CSqlString::GetSortExpression()
{
	int nIndex, nCount;
	SqlString_SortExpression(*this, nIndex, nCount);
	return Mid(nIndex, nCount);
}

void CSqlString::SetSearchCondition(LPCTSTR lpszCondition, BOOL bCompute /* = FALSE */)
{
	int nIndex, nCount;
	if (!SqlString_SearchCondition(*this, nIndex, nCount, bCompute))
		SqlString_Insert(*this, nIndex, bCompute ? _T("having ") : _T("where "));
	SqlString_Stuff(*this, nIndex, nCount, lpszCondition);
}

void CSqlString::SetGroupByExpression(LPCTSTR lpszExpression)
{
	int nIndex, nCount;
	if (!SqlString_GroupByExpression(*this, nIndex, nCount))
		SqlString_Insert(*this, nIndex, _T("group by "));
	SqlString_Stuff(*this, nIndex, nCount, lpszExpression);
}

void CSqlString::SetSortExpression(LPCTSTR lpszExpression)
{
	int nIndex, nCount;
	if (!SqlString_SortExpression(*this, nIndex, nCount))
		SqlString_Insert(*this, nIndex, _T("order by "));
	SqlString_Stuff(*this, nIndex, nCount, lpszExpression);
}

//
//
//
//// CXmlString。
//// 有关类定义的信息，请参阅 DataLink.h
//
//CXmlString::CXmlString()
//{ 
//}
//
//CXmlString::CXmlString(const CString& stringSrc) : CString(stringSrc)
//{
//}
//
//CXmlString::CXmlString(LPCTSTR lpsz) : CString(lpsz)
//{
//}
//
//CXmlString::CXmlString(LPCTSTR lpch, int nLength) : CString(lpch, nLength)
//{
//}
//
//CXmlString::~CXmlString()
//{
//}
//
//void CXmlString::SetAttribute(LPCTSTR keyName, LPCTSTR value)
//{
//	LPCTSTR lpchLeft, lpchRight;
//	lpchLeft = lpchRight = LPCTSTR(*this);
//	TCHAR szKeyName[_MAX_PATH], szValue[_MAX_PATH];
//	while (lpchRight != NULL)
//	{
//		lpchRight = _tsplitattr(lpchRight, szKeyName, NULL, _T(' '));
//		if (_tcsicmp(szKeyName, keyName) == 0)
//			break;
//		lpchLeft = lpchRight;
//	}
//
//	_tcscpy2(szKeyName, keyName, _T('='));
//	_tcscpy2(szValue, value, _T('\"'));
//	CString strItem;
//	if (_tcscspn(value, _T(" \'\"")) < (size_t)lstrlen(value))
//		strItem.Format(_T(" %s=\"%s\" "), szKeyName, szValue);
//	else
//		strItem.Format(_T(" %s=%s "), szKeyName, szValue);
//
//	int nStart = (lpchLeft == NULL) ? GetLength() : (int)(lpchLeft - LPCTSTR(*this));
//	int nEnd = (lpchRight == NULL) ? GetLength() : (int)(lpchRight -LPCTSTR(*this));
//	Delete(nStart, nEnd - nStart);
//	Insert(nStart, strItem);
//}
//
//CString CXmlString::GetAttribute(LPCTSTR keyName)
//{
//	CString value;
//	LPCTSTR lpFullString = LPCTSTR(*this);
//	TCHAR szKeyName[1024], szValue[1024];
//	while (lpFullString != NULL)
//	{
//		lpFullString = _tsplitattr(lpFullString, szKeyName, szValue, _T(' '));
//		if (_tcsicmp(szKeyName, keyName) == 0)
//		{
//			value.SetString(szValue);
//			break;
//		}
//	}
//	return value;
//}
//
//CString CXmlString::GetAttributeName(int nIndex)
//{
//	CString keyName;
//	LPCTSTR lpFullString = LPCTSTR(*this);
//	TCHAR szKeyName[_MAX_PATH];
//	while (nIndex >= 0)
//	{
//		if (lpFullString == NULL)
//			return keyName;
//		lpFullString = _tsplitattr(lpFullString, szKeyName, NULL, _T(' '));
//		nIndex--;
//	}
//	keyName.SetString(szKeyName);
//	return keyName;
//}


// CRecordset class 构造/析构函数
IMPLEMENT_DYNAMIC(CRecordset, CObject)

CRecordset::CRecordset(IDispatch* pConnection /*= NULL*/)
{
	m_pRecordset = NULL;
	m_pConnection = pConnection;
	m_bAutoRelease = FALSE;

	// 初始化状态
	m_bBOF = m_bEOF = TRUE;
	m_bScrollable = m_bAppendable = TRUE;
	m_bEOFSeen = m_bDeleted = m_bUpdatable = FALSE;
	m_lCurrentRecord = AFX_CURRENT_RECORD_UNDEFINED;
	m_lRecordCount = 0L;
	m_nFields = m_nParams = 0;
	m_dwOptions = 0;
}

CRecordset::~CRecordset()
{
	// 关闭数据连接
	Close();

	ASSERT(m_pRecordset == NULL);
	if (m_bAutoRelease)
		ASSERT(m_pConnection == NULL);
}

BOOL CRecordset::CanRestart() const
{
	return TRUE;
}

BOOL CRecordset::CanTransact() const
{
	 //ASSERT(m_pDatabase != NULL );
		//if( m_pDatabase == NULL )
		//	AfxThrowUserException();
		//ASSERT(m_pDatabase->IsOpen());
		//return m_pDatabase->m_bTransactions; 
	return TRUE;
}

BOOL CRecordset::CanBookmark() const
{
	//ASSERT_VALID(this);
	//ASSERT(m_pDatabase->IsOpen());

	//if (!(m_dwOptions & useBookmarks) ||
	//	(m_nOpenType == forwardOnly && !(m_dwOptions & useExtendedFetch)))
	//	return FALSE;

	//return m_pDatabase->GetBookmarkPersistence() & SQL_BP_SCROLL;
	return TRUE;
}

BOOL CRecordset::IsOpen() const
{
	_RecordsetPtr pRecordset = (_RecordsetPtr)m_pRecordset;
	ASSERT(pRecordset != NULL);
	return pRecordset->GetState() & adStateOpen;
}

BOOL CRecordset::IsFieldNull(int nIndex)
{
	_RecordsetPtr pRecordset = (_RecordsetPtr)m_pRecordset;
	pRecordset->GetFields()->GetItem(COleVariant((long)nIndex));
	_variant_t var = pRecordset->GetCollect(COleVariant((long)nIndex));
	return (var.vt == VT_EMPTY);
}

BOOL CRecordset::IsFieldNull(LPCTSTR lpszName)
{
	_RecordsetPtr pRecordset = (_RecordsetPtr)m_pRecordset;
	pRecordset->GetFields()->GetItem(lpszName);
	_variant_t var = pRecordset->GetCollect(_variant_t(lpszName));
	return (var.vt == VT_EMPTY);
}

BOOL CRecordset::IsFieldNullable(int nIndex)
{
	return TRUE;
}

BOOL CRecordset::IsFieldNullable(LPCTSTR lpszName)
{
	return TRUE;
}

BOOL CRecordset::Open(LPCTSTR lpszSQL /* = NULL */, DWORD dwOptions /* = NULL*/)
{
	// 打开可用的连接
	if (m_pConnection == NULL)
	{
		_AFX_DATALINK_STATE* pState = _afxDataLinkState.GetData();
		CConnectionString connection = pState->m_pszConnectionString;
		m_pConnection = connection.OpenConnection();
		if (m_pConnection == NULL)	// 连接没有打开
			return FALSE;

		// 数据库连接自动关闭
		m_bAutoRelease = TRUE;
	}

	// 创建记录集对象
	if (m_pRecordset == NULL)
	{
		_RecordsetPtr pRecordset;
		pRecordset.CreateInstance("ADODB.Recordset");
		if (pRecordset == NULL)
		{
			ASSERT(FALSE);
			return FALSE;
		}

		m_pRecordset = pRecordset;
		m_pRecordset->AddRef();
	}

	// 如果 lpszSQL is NULL, 重新打开数据集
	if (lpszSQL != NULL)
		m_strSQL = lpszSQL;

	CursorTypeEnum cursorType = adOpenDynamic;	// 动态
	LockTypeEnum lockType = adLockBatchOptimistic;	// 乐观封锁型 

	_RecordsetPtr pRecordset = (_RecordsetPtr)m_pRecordset;
	// 先关闭已经打开的记录集
	ASSERT(pRecordset != NULL);
	if (pRecordset->GetState() & adStateOpen)
		pRecordset->raw_Close();

	// 打开记录集
	pRecordset->CursorLocation = adUseClient;
	HRESULT _hr = pRecordset->raw_Open(COleVariant(m_strSQL), 
		_variant_t(m_pConnection), cursorType, lockType, adCmdUnknown );
	if (FAILED(_hr))
	{
		_ConnectionPtr pConnection = (_ConnectionPtr)m_pConnection;
		_SetErrorInfo(pConnection->Errors);
		return FALSE;
	}

	m_bBOF = pRecordset->BOF;
	m_bEOF = pRecordset->IsEOF;

	return TRUE;
}

void CRecordset::Cancel()
{
	try
	{
		_RecordsetPtr pRecordset = (_RecordsetPtr)m_pRecordset;
		pRecordset->Cancel();
	}
	catch (_com_error e)
	{
		TRACE(_T("Warning: Cancel发生异常. 错误信息: %s; 描述: %s\n"), e.ErrorMessage(), (LPCTSTR)e.Description());
	} 
}

void CRecordset::Close()
{
	try
	{
		// 关闭数据集
		_RecordsetPtr pRecordset = (_RecordsetPtr)m_pRecordset;
		if (pRecordset != NULL)
		{
			//if (pRecordset->GetEditMode() == adEditNone)
			//	pRecordset->CancelUpdate();
			if (pRecordset->State != adStateClosed)
				pRecordset->Close();

			m_pRecordset->Release();
			m_pRecordset = NULL;
		}

		// 关闭数据链接
		_ConnectionPtr pConnection = (_ConnectionPtr)m_pConnection;
		if (m_bAutoRelease && pConnection != NULL)
		{
			if (pConnection->State != adStateClosed)
				pConnection->Close();

			m_pConnection->Release();
			m_pConnection = NULL;
		}
	}
	catch (_com_error e)
	{
		TRACE(_T("Warning: 关闭记录集发生异常. 错误信息: %s; 描述: %s\n"), e.ErrorMessage(), (LPCTSTR)e.Description());
	}
}

void CRecordset::Move(long nRows, WORD wFetchType /*= SQL_FETCH_RELATIVE*/)
{
	_RecordsetPtr pRecordset = (_RecordsetPtr)m_pRecordset;
	if (pRecordset == NULL)
		return;

	RETCODE nRetCode = 0;
	switch(wFetchType)
	{
	case SQL_FETCH_NEXT:
		pRecordset->raw_MoveNext();
		_AfxSetCur