AddNew Method Example (VC++)

This example uses the AddNew method to create a new record with the specified name.

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

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

// class extracts empid, fname and lastname  
class CEmployeeRs : public CADORecordBinding {  
   BEGIN_ADO_BINDING(CEmployeeRs)  

   // Column empid is the 1st field in the recordset     
   ADO_VARIABLE_LENGTH_ENTRY2(1, adVarChar, m_sz_empid, sizeof(m_sz_empid),   
                              lemp_empidStatus, TRUE)  

   ADO_VARIABLE_LENGTH_ENTRY2(2, adVarChar, m_sz_fname, sizeof(m_sz_fname),   
                              lemp_fnameStatus, TRUE)  

   ADO_VARIABLE_LENGTH_ENTRY2(4, adVarChar, m_sz_lname, sizeof(m_sz_lname),   
                              lemp_lnameStatus, TRUE)  

   END_ADO_BINDING()  

public:  
   CHAR m_sz_empid[10];  
   ULONG lemp_empidStatus;  
   CHAR m_sz_fname[40];  
   ULONG lemp_fnameStatus;  
   CHAR m_sz_lname[41];  
   ULONG lemp_lnameStatus;  
};  

// Function declaration  
inline void TESTHR(HRESULT x) { if FAILED(x) _com_issue_error(x); };  
void AddNewX();  
void PrintProviderError(_ConnectionPtr pConnection);  

inline int myscanf(char* strDest, int n) {      
   char strExBuff[10];  
   char* pstrRet = fgets(strDest, n, stdin);  

   if (pstrRet == NULL)  
      return 0;  

   if (!strrchr(strDest, '\n'))  
      // Exhaust the input buffer.  
      do {  
         fgets(strExBuff, sizeof(strExBuff), stdin);  
      } while (!strrchr(strExBuff, '\n'));  
   else  
      // Replace '\n' with '\0'  
      strDest[strrchr(strDest, '\n') - strDest] = '\0';  

   return strlen(strDest);  
}  

int main() {  
   HRESULT hr = S_OK;  
   if (FAILED(::CoInitialize(NULL)))   
      return -1;  

   if (SUCCEEDED(hr)) {  
      AddNewX();  
      ::CoUninitialize();  
   }  
}  

void AddNewX() {  
   // Define ADO object pointers. Initialize pointers on define.  
   _RecordsetPtr pRstEmployees = NULL;  
   _ConnectionPtr pConnection = NULL;  

   // Define Other variables  
   IADORecordBinding *picRs = NULL;   // Interface Pointer declared.(VC++ Extensions)     
   CEmployeeRs emprs;   // C++ class object     

   HRESULT hr = S_OK;  

   // Replace Data Source value with your server name.  
   _bstr_t strCnn("Provider='sqloledb'; Data Source='My_Data_Source'; Initial Catalog='pubs'; Integrated Security='SSPI';");  
   _bstr_t strId;  
   _bstr_t strMessage;  

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

      // Open employee table   
      TESTHR(pRstEmployees.CreateInstance(__uuidof(Recordset)));  

      // You have to explicitly pass the Cursor type and LockType to the Recordset here  
      pRstEmployees->Open("employee", _variant_t((IDispatch *) pConnection, true),  
                          adOpenKeyset, adLockOptimistic, adCmdTable);  

      // Open IADORecordBinding interface pointer for Binding Recordset to a class      
      TESTHR(pRstEmployees->QueryInterface(__uuidof(IADORecordBinding), (LPVOID*)&picRs));  

      // Bind the Recordset to a C++ Class here     
      TESTHR(picRs->BindToRecordset(&emprs));           

      // Get data from the user.The employee id must be formatted as first,middle and last   
      // initial, five numbers,then M or F to signify the gender. For example, the   
      // employee id for Bill A. Sorensen would be "BAS55555M".   
      printf("Enter Employee Id: ");  
      myscanf(emprs.m_sz_empid, sizeof(emprs.m_sz_empid));  
      strId = emprs.m_sz_empid;  
      printf("Enter First Name: ");  
      myscanf(emprs.m_sz_fname, sizeof(emprs.m_sz_fname));  
      printf("Enter Last Name:");  
      myscanf(emprs.m_sz_lname, sizeof(emprs.m_sz_lname));  

      // Proceed if user entered id, the first and the last name.   

      if (strcmp(emprs.m_sz_empid, "") && strcmp(emprs.m_sz_fname, "") && strcmp(emprs.m_sz_lname, "")) {  
         // This adds a new record to the table     
         // if (FAILED(hr = picRs->AddNew(&emprs)))  
         //_com_issue_error(hr);  
         TESTHR(picRs->AddNew(&emprs));  

         // Show the newly added data  
         printf("New Record: %s  %s  %s \n",\  
            emprs.lemp_empidStatus == adFldOK ? emprs.m_sz_empid : "<NULL>",\  
            emprs.lemp_fnameStatus == adFldOK ? emprs.m_sz_fname : "<NULL>",\  
            emprs.lemp_lnameStatus == adFldOK ? emprs.m_sz_lname : "<NULL>");  
      }  
      else  
         printf("Please enter an employee id, first name and last name.\n");      

      // Delete the new record because this is a demonstration.   
      pConnection->Execute("DELETE FROM EMPLOYEE WHERE emp_id = '" + strId + "'", NULL, adCmdText);  
   }  
   catch(_com_error &e) {  
      // Notify the user of errors if any.  
      _variant_t vtConnect = pRstEmployees->GetActiveConnection();  

      // GetActiveConnection returns connect string if connection  
      // is not open, else returns Connection object.  
      switch(vtConnect.vt) {  
         case VT_BSTR:  
            printf("Error:\n");  
            printf("Code = %08lx\n", e.Error());  
            printf("Message = %s\n", e.ErrorMessage());  
            printf("Source = %s\n", (LPCSTR) e.Source());  
            printf("Description = %s\n", (LPCSTR) e.Description());  
            break;  
         case VT_DISPATCH:  
            PrintProviderError(vtConnect);  
            break;  
         default:  
            printf("Errors occured.");  
            break;  
      }  
   }  

   // Clean up objects before exit.  Release the IADORecordset Interface here     
   if (picRs)  
      picRs->Release();  

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

See Also

AddNew Method (ADO)
Recordset Object (ADO)