Exemple de propriétés ActiveConnection, CommandText, CommandTimeout, CommandType, Size et Direction (VC++)
Cet exemple utilise les propriétés ActiveConnection, CommandText, CommandTimeout, CommandType, Size et Direction pour exécuter une procédure stockée.
Exemple
// BeginActiveConnectionCpp.cpp
// compile with: /EHsc
#import "msado15.dll" no_namespace rename("EOF", "EndOfFile")
#define TESTHR(x) if FAILED(x) _com_issue_error(x)
#include <stdio.h>
#include <ole2.h>
#include "conio.h"
#include "icrsint.h"
// class extracts fname,lastname
class CEmployeeRs : public CADORecordBinding {
BEGIN_ADO_BINDING(CEmployeeRs)
// Column au_id is the 1st field in the recordset
ADO_VARIABLE_LENGTH_ENTRY2(1, adVarChar, m_szau_id, sizeof(m_szau_id),
lau_idStatus, TRUE)
ADO_VARIABLE_LENGTH_ENTRY2(2, adVarChar, m_szau_lname, sizeof(m_szau_lname),
lau_lnameStatus, TRUE)
ADO_VARIABLE_LENGTH_ENTRY2(3, adVarChar, m_szau_fname, sizeof(m_szau_fname),
lau_fnameStatus, TRUE)
END_ADO_BINDING()
public:
CHAR m_szau_id[20];
ULONG lau_idStatus;
CHAR m_szau_fname[40];
ULONG lau_fnameStatus;
CHAR m_szau_lname[40];
ULONG lau_lnameStatus;
};
// Function declaration
void ActiveConnectionX();
void PrintProviderError(_ConnectionPtr pConnection);
int main() {
if ( FAILED(::CoInitialize(NULL)) )
return -1;
ActiveConnectionX();
::CoUninitialize();
}
void ActiveConnectionX() {
HRESULT hr = S_OK;
// Define ADO object pointers, initialize pointers on define. These are in the ADODB:: namespace.
_ConnectionPtr pConnection = NULL;
_CommandPtr pCmdByRoyalty = NULL;
_RecordsetPtr pRstByRoyalty = NULL;
_RecordsetPtr pRstAuthors = NULL;
_ParameterPtr pPrmByRoyalty = NULL;
// Define Other variables
IADORecordBinding *picRs = NULL; // Interface Pointer declared.(VC++ Extensions) TCS(SPA)
CEmployeeRs emprs; // C++ class object TCS(SPA)
_bstr_t strAuthorId;
int intRoyalty;
VARIANT vtroyal;
_bstr_t strCnn("Provider='sqloledb'; Data Source='My_Data_Source'; Initial Catalog='pubs'; Integrated Security='SSPI';");
try {
// Define a command object for a stored procedure.
TESTHR(pConnection.CreateInstance(__uuidof(Connection)));
hr = pConnection->Open(strCnn, "", "", adConnectUnspecified);
TESTHR(pCmdByRoyalty.CreateInstance(__uuidof(Command)));
pCmdByRoyalty->ActiveConnection = pConnection;
pCmdByRoyalty->CommandText = "byRoyalty";
pCmdByRoyalty->CommandType = adCmdStoredProc;
pCmdByRoyalty->CommandTimeout = 15;
// Define stored procedure's input parameter.
printf("Enter Royalty : ");
scanf_s("%d",&intRoyalty);
// Assign Integer value
vtroyal.vt = VT_I2;
vtroyal.iVal = intRoyalty;
TESTHR(pPrmByRoyalty.CreateInstance(__uuidof(Parameter)));
pPrmByRoyalty->Type = adInteger;
pPrmByRoyalty->Size = 3;
pPrmByRoyalty->Direction = adParamInput;
pPrmByRoyalty->Value = vtroyal;
pCmdByRoyalty->Parameters->Append(pPrmByRoyalty);
// Create a recordset by executing a command.
pRstByRoyalty = pCmdByRoyalty->Execute(NULL,NULL,adCmdStoredProc);
// Open the authors table to get author names for display.
TESTHR(pRstAuthors.CreateInstance(__uuidof(Recordset)));
hr = pRstAuthors->Open("authors", strCnn, adOpenForwardOnly, adLockReadOnly, adCmdTable);
// Open an IADORecordBinding interface pointer which we'll use for Binding Recordset to a class
TESTHR(pRstAuthors->QueryInterface(__uuidof(IADORecordBinding), (LPVOID*)&picRs));
// Bind the Recordset to a C++ Class here
TESTHR(picRs->BindToRecordset(&emprs));
// Print current data in the recordset ,adding author names from author table.
printf("Authors With %d Percent Royalty", intRoyalty);
while (!(pRstByRoyalty->EndOfFile)) {
strAuthorId = pRstByRoyalty->Fields->Item["au_id"]->Value;
pRstAuthors->Filter = "au_id = '" + strAuthorId + "'";
printf("\n\t%s, %s %s",emprs.lau_idStatus == adFldOK ? emprs.m_szau_id : "<NULL>",\
emprs.lau_fnameStatus == adFldOK ? emprs.m_szau_fname : "<NULL>",\
emprs.lau_lnameStatus == adFldOK ? emprs.m_szau_lname : "<NULL>");
pRstByRoyalty->MoveNext();
}
}
catch(_com_error &e) {
// Notify the user of errors if any.
_bstr_t bstrSource(e.Source());
_bstr_t bstrDescription(e.Description());
PrintProviderError(pConnection);
printf("Source : %s \n Description : %s \n", (LPCSTR)bstrSource, (LPCSTR)bstrDescription);
}
// Clean up objects before exit. Release the IADORecordset Interface here
if (picRs)
picRs->Release();
if (pRstByRoyalty)
if (pRstByRoyalty->State == adStateOpen)
pRstByRoyalty->Close();
if (pRstAuthors)
if (pRstAuthors->State == adStateOpen)
pRstAuthors->Close();
if (pConnection)
if (pConnection->State == adStateOpen)
pConnection->Close();
}
void PrintProviderError(_ConnectionPtr pConnection) {
// Print Provider Errors from Connection object.
// pErr is a record object in the Connection's Error collection.
ErrorPtr pErr = NULL;
long nCount = 0;
long i = 0;
if ( (pConnection->Errors->Count) > 0) {
nCount = pConnection->Errors->Count;
// Collection ranges from 0 to nCount -1.
for (i = 0 ; i < nCount ; i++) {
pErr = pConnection->Errors->GetItem(i);
printf("Error number: %x\t%s", pErr->Number, (LPCSTR)pErr->Description);
}
}
}
Entrée
25
Exemple de sortie
Authors With 25 Percent Royalty
724-80-9391, Stearns MacFeather
899-46-2035, Anne Ringer
Voir aussi
ActiveConnection, propriété (ADO)
CommandText, propriété (ADO)
CommandTimeout, propriété (ADO)
CommandType, propriété (ADO)
Direction, propriété
Size, propriété (paramètre ADO)
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