--- title: "Delete Method Example (VC++) | Microsoft Docs" ms.prod: sql ms.prod_service: connectivity ms.technology: connectivity ms.custom: "" ms.date: "01/19/2017" ms.reviewer: "" ms.topic: conceptual dev_langs: - "C++" helpviewer_keywords: - "Delete method [ADO], VC++ example" ms.assetid: 7cc78fb5-2701-49dc-bc22-06613b10cecb author: MightyPen ms.author: genemi --- # Delete Method Example (VC++) This example uses the [Delete](../../../ado/reference/ado-api/delete-method-ado-recordset.md) method to remove a specified record from a [Recordset](../../../ado/reference/ado-api/recordset-object-ado.md). ## Example ``` // DeleteMethodExample.cpp // compile with: /EHsc /c #import "msado15.dll" no_namespace rename("EOF", "EndOfFile") #include #include #include #include "icrsint.h" // This Class extracts titleid, lorange, hirange and royalty from the "roysched" table. class CRoySchedRs : public CADORecordBinding { BEGIN_ADO_BINDING(CRoySchedRs) // Column empid is the 1st field in the recordset ADO_VARIABLE_LENGTH_ENTRY2(1, adVarChar, m_sz_titleid, sizeof(m_sz_titleid), lemp_titleidStatus, TRUE) ADO_VARIABLE_LENGTH_ENTRY2(2, adInteger, m_sz_lorange, sizeof(m_sz_lorange), lemp_lorangeStatus, TRUE) ADO_VARIABLE_LENGTH_ENTRY2(3, adInteger, m_sz_hirange, sizeof(m_sz_hirange), lemp_hirangeStatus, TRUE) ADO_VARIABLE_LENGTH_ENTRY2(4, adInteger, m_sz_royalty, sizeof(m_sz_royalty), lemp_royaltyStatus, TRUE) END_ADO_BINDING() public: CHAR m_sz_titleid[10]; ULONG lemp_titleidStatus; ULONG m_sz_lorange; ULONG lemp_lorangeStatus; ULONG m_sz_hirange; ULONG lemp_hirangeStatus; ULONG m_sz_royalty; ULONG lemp_royaltyStatus; }; // Function Declarations. inline void TESTHR(HRESULT x) { if FAILED(x) _com_issue_error(x); }; void DeleteX(); void PrintProviderError(_ConnectionPtr pConnection); void PrintComError(_com_error &e); inline char* mygets(char* strDest, int n) { char strExBuff[10]; char* pstrRet = fgets(strDest, n, stdin); if (pstrRet == NULL) return NULL; 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 pstrRet; } int main() { if ( FAILED(::CoInitialize(NULL)) ) return -1; DeleteX(); ::CoUninitialize(); } void DeleteX() { // Define ADO object pointers. Initialize pointers on define. // These are in the ADODB:: namespace. _RecordsetPtr pRstRoySched = NULL; // Define Other Variables IADORecordBinding *picRs = NULL; // Interface Pointer declared. CRoySchedRs royschrs; // C++ class object char strTitleID[10], strTmpTitleID[10] = ""; long longHiRange = 0; int intRoyalty = 0, intLoRange = 0, cnt = 0; bool blnFound = TRUE; _bstr_t strCnn("Provider='sqloledb'; Data Source='My_Data_Source'; Initial Catalog='pubs'; Integrated Security='SSPI';"); try { // Open RoySched table TESTHR(pRstRoySched.CreateInstance(__uuidof(Recordset))); pRstRoySched->CursorLocation = adUseClient; pRstRoySched->CursorType = adOpenStatic; pRstRoySched->LockType = adLockBatchOptimistic; TESTHR(pRstRoySched->Open("SELECT * FROM roysched WHERE royalty = 20", strCnn, adOpenStatic, adLockBatchOptimistic, adCmdText)); // Prompt for a record to delete. printf("Before delete there are %d titles with 20 percent royalty :\n", pRstRoySched->RecordCount); // Open an IADORecordBinding interface pointer for Binding Recordset to a class. TESTHR(pRstRoySched->QueryInterface(__uuidof(IADORecordBinding), (LPVOID*)&picRs)); // Bind the Recordset to a C++ Class here TESTHR(picRs->BindToRecordset(&royschrs)); while(!(pRstRoySched->EndOfFile)) { printf("%s\n", royschrs.lemp_titleidStatus == adFldOK ? royschrs.m_sz_titleid : ""); pRstRoySched->MoveNext(); } printf("\nEnter the ID of a record to delete: "); mygets(strTitleID, 10); // Converting the title_id to upper case for ( cnt = 0 ; cnt < 10 ; cnt++ ) if ( strTitleID[cnt] != NULL ) if ( IsCharAlpha( strTitleID[cnt]) ) if ( islower( strTitleID[cnt]) ) strTmpTitleID[cnt] = _toupper(strTitleID[cnt]); else strTmpTitleID[cnt] = strTitleID[cnt]; else strTmpTitleID[cnt] = strTitleID[cnt]; // Move to the record and save data so it can be restored. pRstRoySched->PutFilter ("title_id = '" + (_bstr_t)(LPCSTR)strTmpTitleID + "'"); if ( pRstRoySched->RecordCount != 0 ) { intLoRange = royschrs.m_sz_lorange; longHiRange = royschrs.m_sz_hirange; intRoyalty = royschrs.m_sz_royalty; // Delete the record pRstRoySched->Delete(adAffectCurrent); pRstRoySched->UpdateBatch(adAffectCurrent); } else { blnFound = FALSE; printf("This Title ID not available"); } // Show the results. VARIANT varFilter; varFilter.vt = VT_I2; varFilter.iVal = adFilterNone; pRstRoySched->PutFilter (varFilter); pRstRoySched->Requery(-1); // Bind the Recordset to a C++ Class here. TESTHR(picRs->BindToRecordset(&royschrs)); printf("\nAfter delete there are %d titles with 20 percent royalty: ", pRstRoySched->RecordCount); while ( !(pRstRoySched->EndOfFile) ) { printf("\n%s", royschrs.lemp_titleidStatus == adFldOK ? royschrs.m_sz_titleid : ""); pRstRoySched->MoveNext(); } // Restore the data because this is a demonstration. if ( blnFound ) { // Set the final character of the destination string to NULL. royschrs.m_sz_titleid[sizeof(royschrs.m_sz_titleid) - 1] = '\0'; // The source string will get truncated if its length is // longer than the length of the destination string minus one. strncpy_s(royschrs.m_sz_titleid, strTmpTitleID, sizeof(royschrs.m_sz_titleid) - 1); royschrs.m_sz_lorange = intLoRange; royschrs.m_sz_hirange = longHiRange; royschrs.m_sz_royalty = intRoyalty; TESTHR(picRs->AddNew(&royschrs)); pRstRoySched->UpdateBatch(adAffectCurrent); } } catch(_com_error &e) { // Display errors, if any. Pass connection pointer accessed from the Recordset. _variant_t vtConnect = pRstRoySched->GetActiveConnection(); // GetActiveConnection returns connect string if connection // is not open, else returns Connection object. switch(vtConnect.vt) { case VT_BSTR: PrintComError(e); 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 (pRstRoySched) if (pRstRoySched->State == adStateOpen) pRstRoySched->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; 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("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); } ``` ## Sample Input ``` TC4203 ``` ## Sample Output ``` Before delete there are 7 titles with 20 percent royalty : BU2075 MC3021 TC3218 BU1111 MC2222 TC4203 BU7832 Enter the ID of a record to delete: After delete there are 6 titles with 20 percent royalty: BU2075 MC3021 TC3218 BU1111 MC2222 BU7832 ``` ## See Also [Delete Method (ADO Recordset)](../../../ado/reference/ado-api/delete-method-ado-recordset.md) [Recordset Object (ADO)](../../../ado/reference/ado-api/recordset-object-ado.md)