rscgdlg.cpp

ado连接源代码~包括ado和adox的所有基本使用

// RsCgDlg.cpp : implementation file
//

#include "stdafx.h"
#include "RsCgDlg.h"

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

/////////////////////////////////////////////////////////////////////////////
// CRsCgDlg dialog


CRsCgDlg::CRsCgDlg(CWnd* pParent /*=NULL*/)
	: CDialog(CRsCgDlg::IDD, pParent)
{
	// TO DO: Change m_strConnection to point to 
	// proper location of ADBDMod.mdb database file.
	m_strConnection = _T("Provider=Microsoft.JET.OLEDB.4.0;"
						 "Data Source=Demo.mdb" );
	m_strCmdText = _T("Select * From DemoTable");

	m_pRs = NULL;
	m_piAdoRecordBinding = NULL;

	//{{AFX_DATA_INIT(CRsCgDlg)
	//m_lDlgProductID = 0;
	m_strDlgProductName = _T("");
	m_strDlgQuantityPerUnit = _T("");
	//m_dDlgUnitPrice = 0;
	//m_sDlgUnitsInStock = 0;
	//m_sDlgUnitsOnOrder = 0;
	//m_sDlgReorderLevel = 0;
	//}}AFX_DATA_INIT
}

CRsCgDlg::~CRsCgDlg()
{
	if ( m_piAdoRecordBinding ) m_piAdoRecordBinding->Release();
	m_piAdoRecordBinding = NULL;
	m_pRs = NULL;
}

BOOL CRsCgDlg::OnInitDialog()
{
	HRESULT hr = NOERROR;

	CDialog::OnInitDialog();

	try
	{
		m_pRs.CreateInstance(__uuidof(Recordset));

		m_pRs->CursorLocation = adUseClient; 
		m_pRs->Open((LPCTSTR)m_strCmdText, (LPCTSTR)m_strConnection, adOpenKeyset, 
			adLockOptimistic, adCmdText);

		if (FAILED(hr = m_pRs->QueryInterface(__uuidof(IADORecordBinding), (LPVOID *)&m_piAdoRecordBinding)))
			_com_issue_error(hr);
		if (FAILED(hr = m_piAdoRecordBinding->BindToRecordset(this)))
			_com_issue_error(hr);

		RefreshBoundData();
	}
	catch (_com_error &e)
	{
		GenerateError(e.Error(), e.Description());
	}

	return TRUE;
}

void CRsCgDlg::RefreshBoundData()
{
	//if (adFldOK == lProductIDStatus)
	//	m_lDlgProductID = m_lProductID;
	//else
	//	m_lDlgProductID = 0;
	if (adFldOK == lProductNameStatus)
		m_strDlgProductName = m_szProductName;
	else
		m_strDlgProductName = _T("");
	if (adFldOK == lQuantityPerUnitStatus)
		m_strDlgQuantityPerUnit = m_szQuantityPerUnit;
	else
		m_strDlgQuantityPerUnit = _T("");
	//if (adFldOK == lUnitPriceStatus)
	//	m_dDlgUnitPrice = m_dUnitPrice;
	//else
	//	m_dDlgUnitPrice = 0;
	//if (adFldOK == lUnitsInStockStatus)
	//	m_sDlgUnitsInStock = m_sUnitsInStock;
	//else
	//	m_sDlgUnitsInStock = 0;
	//if (adFldOK == lUnitsOnOrderStatus)
	//	m_sDlgUnitsOnOrder = m_sUnitsOnOrder;
	//else
	//	m_sDlgUnitsOnOrder = 0;
	//if (adFldOK == lReorderLevelStatus)
	//	m_sDlgReorderLevel = m_sReorderLevel;
	//else
	//	m_sDlgReorderLevel = 0;

	UpdateData(FALSE);
}

void CRsCgDlg::GenerateError(HRESULT hr, PWSTR pwszDescription)
{
	CString strError;

	strError.Format("Run-time error '%d (%x)'", hr, hr);
	strError += "\n\n";
	strError += pwszDescription;

	AfxMessageBox(strError);
}

void CRsCgDlg::DoDataExchange(CDataExchange* pDX)
{
	CDialog::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CRsCgDlg)
	//DDX_Text(pDX, IDC_EDIT_PRODUCTID, m_lDlgProductID);
	DDX_Text(pDX, IDC_EDIT_PRODUCTNAME, m_strDlgProductName);
	DDX_Text(pDX, IDC_EDIT_QUANTITYPERUNIT, m_strDlgQuantityPerUnit);
	//DDX_Text(pDX, IDC_EDIT_UNITPRICE, m_dDlgUnitPrice);
	//DDX_Text(pDX, IDC_EDIT_UNITSINSTOCK, m_sDlgUnitsInStock);
	//DDX_Text(pDX, IDC_EDIT_UNITSONORDER, m_sDlgUnitsOnOrder);
	//DDX_Text(pDX, IDC_EDIT_REORDERLEVEL, m_sDlgReorderLevel);
	//}}AFX_DATA_MAP
}


BEGIN_MESSAGE_MAP(CRsCgDlg, CDialog)
	//{{AFX_MSG_MAP(CRsCgDlg)
	ON_BN_CLICKED(ID_BTN_MOVEFIRST, OnBtnMoveFirst)
	ON_BN_CLICKED(ID_BTN_MOVELAST, OnBtnMoveLast)
	ON_BN_CLICKED(ID_BTN_MOVENEXT, OnBtnMoveNext)
	ON_BN_CLICKED(ID_BTN_MOVEPREVIOUS, OnBtnMovePrevious)
	ON_BN_CLICKED(IDC_SAVE_RECORD, OnSaveRecord)
	ON_BN_CLICKED(IDC_ADD_RECORD, OnAddRecord)
	ON_BN_CLICKED(IDC_DELETE_RECORD, OnDeleteRecord)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CRsCgDlg message handlers

void CRsCgDlg::OnBtnMoveFirst() 
{
	try
	{
		m_pRs->MoveFirst();
		RefreshBoundData();
	}
	catch (_com_error &e)
	{
		GenerateError(e.Error(), e.Description());
	}
}

void CRsCgDlg::OnBtnMoveLast() 
{
	try
	{
		m_pRs->MoveLast();
		RefreshBoundData();
	}
	catch (_com_error &e)
	{
		GenerateError(e.Error(), e.Description());
	}
}

void CRsCgDlg::OnBtnMoveNext() 
{
	try
	{
		m_pRs->MoveNext();
		RefreshBoundData();
	}
	catch (_com_error &e)
	{
		GenerateError(e.Error(), e.Description());
	}
}

void CRsCgDlg::OnBtnMovePrevious() 
{
	try
	{
		m_pRs->MovePrevious();
		RefreshBoundData();
	}
	catch (_com_error &e)
	{
		GenerateError(e.Error(), e.Description());
	}
}


BOOL CRsCgDlg::IsDirty()
{
	// Skip if recordset not ready.
	if ( NULL == m_pRs ) return FALSE;

	// Pull data into dialog member variables.
	UpdateData( TRUE );

	// Compare dialog members with binding members.
	//if ( m_lProductID != m_lDlgProductID ) return TRUE;
	if ( m_strDlgProductName.Compare( m_szProductName ) ) return TRUE;
	if ( m_strDlgQuantityPerUnit.Compare( m_szQuantityPerUnit ) ) return TRUE;
	//if ( m_dUnitPrice != m_dDlgUnitPrice ) return TRUE;
	//if ( m_sUnitsInStock != m_sDlgUnitsInStock ) return TRUE;
	//if ( m_sUnitsOnOrder != m_sDlgUnitsOnOrder ) return TRUE;
	//if ( m_sReorderLevel != m_sDlgReorderLevel ) return TRUE;

	return FALSE;
}

void CRsCgDlg::PrepareBoundData()
{
	// Copies data from dialog member variables into
	// ADO C++ binding member variables in order to 
	// prepare ADO C++ binding for AddNew or Update.

	// Skip if recordset not ready.
	if ( NULL == m_pRs ) return;

	// Pull data into dialog member variables.
	UpdateData( TRUE );
	
	// Copy dialog members into ADO C++ binding members.
	//m_lProductID = m_lDlgProductID;
	//lProductIDStatus = adFldOK;

	// For strings, copy data and then check for zero-length.
	// Set the field status to adFldNull to indicate the field 
	// should be set to null if the length of the string is zero.
	strncpy( m_szProductName, m_strDlgProductName, sizeof(m_szProductName) );
	lProductNameStatus = (0==strlen(m_szProductName)) ? adFldNull : adFldOK;

	strncpy( m_szQuantityPerUnit, m_strDlgQuantityPerUnit, sizeof(m_szQuantityPerUnit) );
	lQuantityPerUnitStatus = (0==strlen(m_szQuantityPerUnit)) ? adFldNull : adFldOK;
	
	//m_dUnitPrice = m_dDlgUnitPrice;
	//lUnitPriceStatus = adFldOK;

	//m_sUnitsInStock = m_sDlgUnitsInStock;
	//lUnitsInStockStatus = adFldOK;

	//m_sUnitsOnOrder = m_sDlgUnitsOnOrder;
	//lUnitsOnOrderStatus = adFldOK;

	//m_sReorderLevel = m_sDlgReorderLevel;
	//lReorderLevelStatus = adFldOK;

}

void CRsCgDlg::SaveRecord()
{
	// Skip if recordset not ready.
	if ( NULL == m_pRs ) return;

	// Copy data from dialog into ADO C++ binding members.
	PrepareBoundData();

	// Call Update method of IADORecordBinding interface,
	// passing in dialog class which doubles as our CADORecordBinding structure.
	HRESULT hr = m_piAdoRecordBinding->Update( (CADORecordBinding*)this );
	if ( FAILED(hr) ) 
	{
		TraceADOErrors();
		TraceFieldStatus();
		GenerateError( hr, L"CRsCgDlg::SaveRecord() Failed." );
	}
	RefreshBoundData();
}

void CRsCgDlg::AddRecord()
{
	// Skip if recordset not ready.
	if ( NULL == m_pRs ) return;

	// 资料复制到对话框到C + +中使用ADO成员具有约束力
	PrepareBoundData();

	// Call AddNew method of IADORecordBinding interface,
	// passing in dialog class which doubles as our CADORecordBinding structure.
	HRESULT hr = m_piAdoRecordBinding->AddNew( (CADORecordBinding*)this );
	if ( FAILED(hr) ) 
	{
		TraceADOErrors();
		TraceFieldStatus();
		GenerateError( hr, L"CRsCgDlg::AddRecord() Failed." );
	}
	RefreshBoundData();
}

void CRsCgDlg::OnSaveRecord() 
{
	// Check if record is dirty, then save record.
	if ( IsDirty() )
	{
		SaveRecord();
	}
}

void CRsCgDlg::OnAddRecord() 
{
	AddRecord();
}

void CRsCgDlg::OnDeleteRecord() 
{
	// Skip if recordset not ready.
	if ( NULL == m_pRs ) return;

	// Delete record and refresh recordset.
	m_pRs->Delete( adAffectCurrent );
	OnBtnMoveFirst();
}

void CRsCgDlg::TraceFieldStatus()
{
	// Generic code to trace the status flag for each
	// field in the ADO binding structure.

	// By checking the field status indicators, you can
	// see which field(s) caused errors during an
	// AddNew or Update call.

	const char* szStatus[] = { "adFldOK","adFldBadAccessor","adFldCantConvertValue","adFldNull",
			"adFldTruncated","adFldSignMismatch","adFldDataOverFlow","adFldCantCreate",
			"adFldUnavailable","adFldPermissionDenied","adFldIntegrityViolation",
			"adFldSchemaViolation","adFldBadStatus","adFldDefault" };

	// Note: GetADOBindingEntries is defined by the BEGIN_ADO_BINDING macro.
	// It returns a pointer to an array of ADO_BINDING_ENTRY records.
	// The END_ADO_BINDING() macro adds the last array entry and sets the
	// ulOrdinal member to 0 so you can use this member to check for the
	// end of the array.

	const ADO_BINDING_ENTRY* pBindingArray = GetADOBindingEntries();
	CCustomRs* pBindingClass = (CCustomRs*) this;

	TRACE( _T("Listing ADO VC++ Binding field status information:\n") );
	while ( pBindingArray->ulOrdinal )
	{
		TRACE( _T("Field[%d].Status=%s\n"), 
			   pBindingArray->ulOrdinal, 
			   szStatus[ *( (ULONG*) (((BYTE*)pBindingClass) + pBindingArray->ulStatusOffset) ) ] );
		pBindingArray++;
	}

}

void CRsCgDlg::TraceADOErrors()
{
	// Generic code for looping through ADO errors collection.

	// Skip if recordset not ready.
	if ( NULL == m_pRs ) return;

	_ConnectionPtr conn = NULL;

	// Cast _variant_t -> IDispatch* -> _Connection*
	// These casts result in QueryInterface calls since we
	// are using smart pointers.
	conn = (_Connection *) (IDispatch*) m_pRs->GetActiveConnection();

	ErrorPtr err;
	TRACE( _T("Listing ADO Errors collection:\n") );
	for ( long i=0; i<conn->Errors->Count; i++ )
	{
		err = conn->Errors->Item[i];
		TRACE( _T("Err[%lu].Number     : 0x%08x\n"), i, err->Number );
		// Cast _bstr_t to char* to do BSTR -> ANSI string conversion.
		TRACE( _T("Err[%lu].Description: %s\n"), i, (char*) err->Description );
	}

}