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Applies to: Access 2013, Office 2013
This example demonstrates the Source property by opening three Recordset objects based on different data sources.
// BeginSourceCpp
#import "c:\Program Files\Common Files\System\ADO\msado15.dll" no_namespace rename("EOF", "EndOfFile")
#include <ole2.h>
#include <stdio.h>
#include <conio.h>
// Function declarations
inline void TESTHR(HRESULT x) {if FAILED(x) _com_issue_error(x);};
void SourceX(void);
void PrintProviderError(_ConnectionPtr pConnection);
void PrintComError(_com_error &e);
///////////////////////////
// //
// Main Function //
// //
///////////////////////////
void main()
{
if(FAILED(::CoInitialize(NULL)))
return;
SourceX();
::CoUninitialize();
}
///////////////////////////////////////////////
// //
// SourceX Function //
// //
///////////////////////////////////////////////
void SourceX(void)
{
HRESULT hr = S_OK;
// Define string variables.
_bstr_t strCmdSQL("Select title,type,pubdate "
"FROM titles ORDER BY title");
_bstr_t strSQL("SELECT title_ID AS TitleID, title AS Title, "
"publishers.pub_id AS PubID, pub_name AS PubName "
"FROM publishers INNER JOIN titles "
"ON publishers.pub_id = titles.pub_id "
"ORDER BY Title");
_bstr_t strCnn("Provider='sqloledb';Data Source='MySqlServer';"
"Initial Catalog='pubs';Integrated Security='SSPI';");
// Define ADO object pointers.
// Initialize pointers on define.
// These are in the ADODB:: namespace.
_ConnectionPtr pConnection = NULL;
_RecordsetPtr pRstTitles = NULL;
_RecordsetPtr pRstPublishers = NULL;
_RecordsetPtr pRstPublishersDirect = NULL;
_RecordsetPtr pRstTitlesPublishers = NULL;
_CommandPtr pCmdSQL = NULL;
try
{
// Open a connection.
TESTHR(pConnection.CreateInstance(__uuidof(Connection)));
pConnection->Open (strCnn, "", "", adConnectUnspecified);
// Open a recordset based on a command object.
TESTHR(pCmdSQL.CreateInstance(__uuidof(Command)));
pCmdSQL->ActiveConnection = pConnection;
pCmdSQL->CommandText = strCmdSQL;
pRstTitles = pCmdSQL->Execute(NULL,NULL,adCmdText);
// Open a recordset based on a a table
TESTHR(pRstPublishers.CreateInstance(__uuidof(Recordset)));
pRstPublishers->Open ("publishers",
_variant_t((IDispatch *) pConnection, true),
adOpenForwardOnly, adLockReadOnly, adCmdTable);
// Open a recordset based on a table
TESTHR(pRstPublishersDirect.CreateInstance(
__uuidof(Recordset)));
pRstPublishersDirect->Open ("publishers",
_variant_t((IDispatch *) pConnection, true),
adOpenForwardOnly, adLockReadOnly, adCmdTableDirect);
// Open a recordset based on a SQL string.
TESTHR(pRstTitlesPublishers.CreateInstance(
__uuidof(Recordset)));
pRstTitlesPublishers->Open(strSQL,
_variant_t((IDispatch *) pConnection, true),
adOpenForwardOnly, adLockReadOnly, adCmdText);
// Use the Source property to display the source of
// each recordset.
printf("rstTitles source: \n%s\n\n",
(LPCSTR)(_bstr_t) pRstTitles->GetSource().bstrVal);
printf("rstPublishers source: \n%s\n\n",
(LPCSTR)(_bstr_t) pRstPublishers->GetSource().bstrVal);
printf("rstPublishersDirect source: \n%s\n\n",
(LPCSTR)(_bstr_t) pRstPublishersDirect->GetSource().bstrVal);
printf("rstTitlesPublishers source: \n%s\n\n",
(LPCSTR)(_bstr_t) pRstTitlesPublishers->GetSource().bstrVal);
}
catch (_com_error &e)
{
// Notify the user of errors if any.
PrintProviderError(pConnection);
PrintComError(e);
}
if (pRstTitles)
if (pRstTitles->State == adStateOpen)
pRstTitles->Close();
if (pRstPublishers)
if (pRstPublishers->State == adStateOpen)
pRstPublishers->Close();
if (pRstPublishersDirect)
if (pRstPublishersDirect->State == adStateOpen)
pRstPublishersDirect->Close();
if (pRstTitlesPublishers)
if (pRstTitlesPublishers->State == adStateOpen)
pRstTitlesPublishers->Close();
if (pConnection)
if (pConnection->State == adStateOpen)
pConnection->Close();
}
///////////////////////////////////////////////
// //
// PrintProviderError Function //
// //
///////////////////////////////////////////////
void PrintProviderError(_ConnectionPtr pConnection)
{
// Print Provider Errors from Connection object.
// pErr is a record object in the Connection's Error collection.
ErrorPtr pErr = NULL;
if( (pConnection->Errors->Count) > 0)
{
long nCount = pConnection->Errors->Count;
// Collection ranges from 0 to nCount -1.
for(long i = 0; i < nCount; i++)
{
pErr = pConnection->Errors->GetItem(i);
printf("Error number: %x\t%s\n", pErr->Number,
(LPCSTR) pErr->Description);
}
}
}
///////////////////////////////////////////////
// //
// PrintComError Function //
// //
///////////////////////////////////////////////
void PrintComError(_com_error &e)
{
_bstr_t bstrSource(e.Source());
_bstr_t bstrDescription(e.Description());
// Print Com errors.
printf("Error\n");
printf("\tCode = %08lx\n", e.Error());
printf("\tCode meaning = %s\n", e.ErrorMessage());
printf("\tSource = %s\n", (LPCSTR) bstrSource);
printf("\tDescription = %s\n", (LPCSTR) bstrDescription);
}
// EndSourceCpp