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CursorType, LockType, and EditMode Properties Example (VC++)

This example demonstrates setting the CursorType and LockType properties before opening a Recordset. It also shows the value of the EditMode property under various conditions. The EditModeOutput function is required for this procedure to run.

// CursorType_LockType_EditMode_Property_Example.cpp
// compile with: /EHsc
#import "msado15.dll" no_namespace rename("EOF", "EndOfFile")

#include <ole2.h>
#include <stdio.h>
#include <conio.h>

// Function declaration
inline void TESTHR(HRESULT x) { if FAILED(x) _com_issue_error(x); };
void EditModeX();
void EditModeOutput(char *, int);
void PrintProviderError(_ConnectionPtr pConnection);
void PrintComError(_com_error &e);

int main() {
   if ( FAILED(::CoInitialize(NULL)) )
      return -1;

   EditModeX();
   ::CoUninitialize();
}

void EditModeX() {
   // Define ADO object pointers.  Initialize pointers on define.
   // These are in the ADODB:: namespace.
   _RecordsetPtr pRstEmployees = NULL;
   _ConnectionPtr pConnection = NULL;

   HRESULT hr = S_OK;

   _bstr_t strCnn("Provider='sqloledb'; Data Source='My_Data_Source'; Initial Catalog='pubs'; Integrated Security='SSPI';");

   try {
      // Open a connection
      TESTHR(pConnection.CreateInstance(__uuidof(Connection)));
      hr = pConnection->Open(strCnn, "", "", adConnectUnspecified);

      // Open recordset with data from employee table 
      TESTHR(pRstEmployees.CreateInstance(__uuidof(Recordset)));

      pRstEmployees->CursorLocation = adUseClient;
      pRstEmployees->CursorType = adOpenStatic;
      pRstEmployees->LockType = adLockBatchOptimistic;

      pRstEmployees->Open("employee", _variant_t((IDispatch *) pConnection,true),
         adOpenStatic, adLockBatchOptimistic, adCmdTable);

      // Show the EditMode property under different editing states.
      pRstEmployees->AddNew ();
      pRstEmployees->Fields->Item["emp_id"]->Value = (_bstr_t)("T-T55555M");
      pRstEmployees->Fields->Item["fname"]->Value = (_bstr_t)("temp_fname");
      pRstEmployees->Fields->Item["lname"]->Value = (_bstr_t)("temp_lname");
      EditModeOutput("After AddNew: ", pRstEmployees->EditMode);

      pRstEmployees->UpdateBatch(adAffectCurrent);
      EditModeOutput("After Update: ", pRstEmployees->EditMode);

      pRstEmployees->Fields->Item["fname"]->Value = (_bstr_t)("test");
      EditModeOutput("After Edit: ", pRstEmployees->EditMode);

      // Delete new record because this is a demonstration.
      pConnection->Execute("DELETE FROM employee WHERE emp_id = 'T-T55555M'", 
         NULL, adCmdText);
   }
   catch(_com_error &e) {
      // Display errors, if any. Pass connection pointer accessed from the Recordset.
      PrintProviderError(pConnection);
      PrintComError(e);
   }

   // Clean up objects before exit.
   if (pRstEmployees)
      if (pRstEmployees->State == adStateOpen)
         pRstEmployees->Close();
   if (pConnection)
      if (pConnection->State == adStateOpen)
         pConnection->Close();
}

void EditModeOutput(char *strTemp, int intEditMode) {
   // Print report based on the value of the EditMode property.
   printf("\n%s", strTemp);
   printf("\n  EditMode = ");

   switch (intEditMode) {
   case adEditNone :
      printf("adEditNone");
      break;
   case adEditInProgress :
      printf("adEditInProgress");
      break;
   case adEditAdd :
      printf("adEditAdd");
      break;
   }
}

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("\n\t Error number: %x\t%s\n", pErr->Number, (LPCSTR)pErr->Description);
      }
   }
}

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);
}
After AddNew: 
  EditMode = adEditAdd
After Update: 
  EditMode = adEditNone
After Edit: 
  EditMode = adEditInProgress
Show:
© 2015 Microsoft