GETRDLG.CPP

//-------------------------------------------------------------------- 
// Microsoft ADO Samples 
// 
// (c) 1996 Microsoft Corporation.  All Rights Reserved. 
// 
// @doc GetRows Sample 
// 
// @modulegetrdlg.cpp 
// 
// @devnote None 
//-------------------------------------------------------------------- 
 
#include "stdafx.h" 
#include "GetRows.h" 
#include "GetRDlg.h" 
 
const LPCTSTR x_lpcszSource = _T("OLE_DB_NWind_Jet"); 
const LPCTSTR x_lpcszUser = _T("Admin");     
const LPCTSTR x_lpcszPassword = _T(""); 
const LPCTSTR x_lpcszSQL = _T("select EmployeeId, LastName, FirstName from Employees"); 
 
///////////////////////////////////////////////////////////////////////////// 
// CAboutDlg dialog used for App About 
 
class CAboutDlg : public CDialog 
{ 
public: 
CAboutDlg(); 
 
// Dialog Data 
//{{AFX_DATA(CAboutDlg) 
enum { IDD = IDD_ABOUTBOX }; 
//}}AFX_DATA 
 
// ClassWizard generated virtual function overrides 
//{{AFX_VIRTUAL(CAboutDlg) 
protected: 
virtual void DoDataExchange(CDataExchange* pDX);    // DDX/DDV support 
//}}AFX_VIRTUAL 
 
// Implementation 
protected: 
//{{AFX_MSG(CAboutDlg) 
//}}AFX_MSG 
DECLARE_MESSAGE_MAP() 
}; 
 
CAboutDlg::CAboutDlg() : CDialog(CAboutDlg::IDD) 
{ 
//{{AFX_DATA_INIT(CAboutDlg) 
//}}AFX_DATA_INIT 
} 
 
void CAboutDlg::DoDataExchange(CDataExchange* pDX) 
{ 
CDialog::DoDataExchange(pDX); 
//{{AFX_DATA_MAP(CAboutDlg) 
//}}AFX_DATA_MAP 
} 
 
BEGIN_MESSAGE_MAP(CAboutDlg, CDialog) 
 //{{AFX_MSG_MAP(CAboutDlg) 
//}}AFX_MSG_MAP 
END_MESSAGE_MAP() 
 
///////////////////////////////////////////////////////////////////////////// 
// CGetRowsDlg dialog 
 
CGetRowsDlg::CGetRowsDlg(CWnd* pParent /*=NULL*/) 
: CDialog(CGetRowsDlg::IDD, pParent) 
{ 
//{{AFX_DATA_INIT(CGetRowsDlg) 
// NOTE: the ClassWizard will add member initialization here 
//}}AFX_DATA_INIT 
// Note that LoadIcon does not require a subsequent DestroyIcon in Win32 
m_hIcon = AfxGetApp()->LoadIcon(IDR_MAINFRAME); 
m_piConnection = NULL; 
m_piEmpRecordSet = NULL; 
m_strSource = x_lpcszSource; 
m_strUser = x_lpcszUser; 
m_strPassword = x_lpcszPassword; 
m_strSQL = x_lpcszSQL; 
} 
 
CGetRowsDlg::~CGetRowsDlg() 
{ 
if ( m_piConnection != NULL ) 
m_piConnection->Release();  
if ( m_piEmpRecordSet != NULL ) 
m_piEmpRecordSet->Release(); 
m_piConnection = NULL; 
m_piEmpRecordSet = NULL; 
} 
 
 
void CGetRowsDlg::DoDataExchange(CDataExchange* pDX) 
{ 
CDialog::DoDataExchange(pDX); 
//{{AFX_DATA_MAP(CGetRowsDlg) 
// NOTE: the ClassWizard will add DDX and DDV calls here 
//}}AFX_DATA_MAP 
} 
 
BEGIN_MESSAGE_MAP(CGetRowsDlg, CDialog) 
//{{AFX_MSG_MAP(CGetRowsDlg) 
ON_WM_SYSCOMMAND() 
ON_WM_PAINT() 
ON_WM_QUERYDRAGICON() 
ON_BN_CLICKED(IDD_EXECUTE, OnExecute) 
//}}AFX_MSG_MAP 
END_MESSAGE_MAP() 
 
///////////////////////////////////////////////////////////////////////////// 
// CGetRowsDlg message handlers 
 
BOOL CGetRowsDlg::OnInitDialog() 
{ 
CDialog::OnInitDialog(); 
 
// Add "About..." menu item to system menu. 
 
// IDM_ABOUTBOX must be in the system command range. 
ASSERT((IDM_ABOUTBOX & 0xFFF0) == IDM_ABOUTBOX); 
ASSERT(IDM_ABOUTBOX < 0xF000); 
 
CMenu* pSysMenu = GetSystemMenu(FALSE); 
CString strAboutMenu; 
strAboutMenu.LoadString(IDS_ABOUTBOX); 
if (!strAboutMenu.IsEmpty()) 
{ 
pSysMenu->AppendMenu(MF_SEPARATOR); 
pSysMenu->AppendMenu(MF_STRING, IDM_ABOUTBOX, strAboutMenu); 
} 
 
// Set the icon for this dialog.  The framework does this automatically 
//  when the application's main window is not a dialog 
SetIcon(m_hIcon, TRUE);// Set big icon 
SetIcon(m_hIcon, FALSE);// Set small icon 
 
return TRUE;  // return TRUE  unless you set the focus to a control 
} 
 
void CGetRowsDlg::OnSysCommand(UINT nID, LPARAM lParam) 
{ 
if ((nID & 0xFFF0) == IDM_ABOUTBOX) 
{ 
CAboutDlg dlgAbout; 
dlgAbout.DoModal(); 
} 
else 
{ 
CDialog::OnSysCommand(nID, lParam); 
} 
} 
 
// If you add a minimize button to your dialog, you will need the code below 
//  to draw the icon.  For MFC applications using the document/view model, 
//  this is automatically done for you by the framework. 
 
void CGetRowsDlg::OnPaint()  
{ 
if (IsIconic()) 
{ 
CPaintDC dc(this); // device context for painting 
 
SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0); 
 
// Center icon in client rectangle 
int cxIcon = GetSystemMetrics(SM_CXICON); 
int cyIcon = GetSystemMetrics(SM_CYICON); 
CRect rect; 
GetClientRect(&rect); 
int x = (rect.Width() - cxIcon + 1) / 2; 
int y = (rect.Height() - cyIcon + 1) / 2; 
 
// Draw the icon 
dc.DrawIcon(x, y, m_hIcon); 
} 
else 
{ 
CDialog::OnPaint(); 
} 
} 
 
// The system calls this to obtain the cursor to display while the user drags 
//  the minimized window. 
HCURSOR CGetRowsDlg::OnQueryDragIcon() 
{ 
return (HCURSOR) m_hIcon; 
} 
 
 
void CGetRowsDlg::OnExecute()  
{ 
BSTRbstrSource = NULL; 
BSTRbstrUser = NULL; 
BSTRbstrPassword = NULL; 
BSTRbstrSQL = NULL; 
HRESULThr; 
COleVariantvNull; 
 
//Open the database and the recordset 
if ( m_piConnection == NULL || m_piEmpRecordSet == NULL) 
{ 
hr = CoInitialize(NULL); 
if (FAILED(hr))goto ErrorExit; 
 
hr = CoCreateInstance(CLSID_CADOConnection, NULL, CLSCTX_INPROC_SERVER, IID_IADOConnection, (LPVOID *)&m_piConnection); 
if (FAILED(hr))goto ErrorExit; 
 
bstrSource = m_strSource.AllocSysString(); 
bstrUser = m_strUser.AllocSysString(); 
bstrPassword = m_strPassword.AllocSysString(); 
bstrSQL = m_strSQL.AllocSysString(); 
if ( bstrSource == NULL || bstrUser == NULL || bstrSQL == NULL ) 
goto ErrorExit; 
 
hr = m_piConnection->Open( bstrSource, bstrUser, bstrPassword );  
 if (FAILED(hr))goto ErrorExit; 
 
 
  hr = CoCreateInstance(CLSID_CADORecordset, NULL, CLSCTX_INPROC_SERVER, IID_IADORecordset, (LPVOID *)&m_piEmpRecordSet); 
if (FAILED(hr))goto ErrorExit; 
 
hr = m_piEmpRecordSet->put_Source(bstrSQL); 
if (FAILED(hr))goto ErrorExit; 
 
hr = m_piEmpRecordSet->putref_ActiveConnection(m_piConnection); 
if (FAILED(hr))goto ErrorExit; 
 
vNull.vt = VT_ERROR; 
vNull.scode = DISP_E_PARAMNOTFOUND; 
hr = m_piEmpRecordSet->Open(vNull, vNull, adOpenKeyset, adLockOptimistic, adCmdUnknown); 
if (FAILED(hr))goto ErrorExit; 
} 
 
// Perform the two GetRows functions 
hr = DoGetRows(); 
 if (FAILED(hr))goto ErrorExit; 
 
// Reset the recordset 
m_piEmpRecordSet->MoveFirst(); 
 
SysFreeString(bstrSource); 
SysFreeString(bstrUser);  
SysFreeString(bstrPassword); 
SysFreeString(bstrSQL); 
 
return ; 
 
ErrorExit: 
TCHAR szBuf[256]; 
wsprintf(szBuf, _T("Error: %d \n"), hr); 
AfxMessageBox(szBuf); 
 
SysFreeString(bstrSource); 
SysFreeString(bstrUser); 
SysFreeString(bstrPassword); 
SysFreeString(bstrSQL); 
return ; 
} 
 
 
// Perform standard GetRows against the Employee table 
HRESULT CGetRowsDlg::DoGetRows()  
{ 
HRESULThr; 
COleVariantvBookmark, rgvFields; 
COleVariantcRows; 
COleVariantvarField, varNewField; 
CStringstrLBRow; 
LONGlNumOfCol, lNumRecords; 
LONGlIndex[2]; 
CListBox*pListBox = (CListBox *)GetDlgItem(IDD_GETROWSLIST); 
 
//Perform GetRows on Employee table 
 
//Start from the current place  
vBookmark.vt = VT_ERROR; 
vBookmark.scode = DISP_E_PARAMNOTFOUND; 
 
//Get all columns.     
rgvFields.vt = VT_ERROR; 
rgvFields.scode = DISP_E_PARAMNOTFOUND; 
 
if (!m_piEmpRecordSet) 
return E_NOINTERFACE; 
 
hr = m_piEmpRecordSet->GetRows(adGetRowsRest, //MAX_EMP_REC,// non-optional,  
vBookmark, 
rgvFields, 
&cRows  
); 
if (FAILED(hr)) goto ErrorExit; 
 
 
//Find out how many records were actually retrieved 
//(SafeArrays are 1-based) 
lNumOfCol = 2; 
SafeArrayGetUBound(cRows.parray, 2, &lNumRecords); 
 
//Clear the listbox 
pListBox->ResetContent(); 
 
for (lIndex[1] = 0; lIndex[1] <= lNumRecords; lIndex[1]++) 
{ 
strLBRow.Empty();//Clear the string 
 
for (lIndex[0] = 0; lIndex[0] <= lNumOfCol; lIndex[0]++)   // get 3 columns 
{ 
SafeArrayGetElement(cRows.parray, &lIndex[0], &varField); 
 
hr = VariantChangeType(&varNewField, &varField, 0, VT_BSTR); 
 
if(hr == S_OK) 
{ 
strLBRow += (LPCWSTR)varNewField.bstrVal; 
strLBRow += _T(", "); 
} 
varField.Clear(); 
varNewField.Clear(); 
} 
pListBox->AddString(strLBRow); 
} 
 
return hr; 
 
ErrorExit: 
TCHAR szBuf[256]; 
wsprintf(szBuf, _T("Error: %d \n"), hr); 
AfxMessageBox(szBuf); 
 
return hr; 
}