ActiveConnection-, CommandText-, CommandTimeout-, CommandType-, Size- und Direction-Eigenschaft (Beispiel) (VC++)
Gilt für: Access 2013, Office 2013
In diesem Beispiel wird mithilfe der Eigenschaften ActiveConnection, CommandText, CommandTimeout, CommandType, Size und Direction eine gespeicherte Prozedur ausgeführt.
// BeginActiveConnectionCpp
#import "C:\Program Files\Common Files\System\ADO\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 "ActiveConnectionX.h"
//Function declaration
void ActiveConnectionX(VOID);
void PrintProviderError(_ConnectionPtr pConnection);
///////////////////////////////////////////////////////////
// //
// Main Function //
// //
///////////////////////////////////////////////////////////
void main()
{
if(FAILED(::CoInitialize(NULL)))
return;
ActiveConnectionX();
//Wait here for user to see the output..
printf("\n\nPress any key to continue..");
getch();
::CoUninitialize();
}
///////////////////////////////////////////////////////////
// //
// ActiveConnectionX Function //
// //
///////////////////////////////////////////////////////////
VOID ActiveConnectionX(VOID)
{
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='MySqlServer';"
"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("%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();
}
///////////////////////////////////////////////////////////
// //
// 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;
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);
}
}
}
// EndActiveConnectionCpp
ActiveConnectionX.h
// BeginActiveConnectionH
#include "icrsint.h"
//This 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;
};
// EndActiveConnectionH