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AddNew Method Example (VC++)

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

// BeginAddNewCpp
#import "msado15.dll" \
    no_namespace rename("EOF", "EndOfFile")


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

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

///////////////////////////////////////////////////////////
//                                                       //
//      Main Function                                    //
//                                                       //
///////////////////////////////////////////////////////////
void main()
{
    HRESULT  hr = S_OK;

    if(FAILED(::CoInitialize(NULL))) 
        return; 

    if (SUCCEEDED(hr))
    {
         AddNewX();

        //Wait here for the user to see the output
        printf("Press any key to continue...");
        getch();

        ::CoUninitialize();
    }
}


///////////////////////////////////////////////////////////
//                                                       //
//      AddNewX Function                                 //
//                                                       //
///////////////////////////////////////////////////////////
VOID AddNewX(VOID)
{

    // 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='MySqlServer';"
        "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 an IADORecordBinding interface pointer which we'll use 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 the user actually entered some thing  
        //for the 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();
}


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

AddNewX.h:

// BeginAddNewH
#include "icrsint.h"


//This 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;

};
// EndAddNewH

See Also

AddNew Method | Recordset Object