Status プロパティの使用例 (VC++)

適用先: Access 2013、Office 2013

この例では、Status プロパティを使用して、一括更新の前にバッチ処理で変更されたレコードを表示します。

 
// BeginStatusCpp 
#import "c:\Program Files\Common Files\System\ADO\msado15.dll" no_namespace rename("EOF", "EndOfFile") 
 
#include <ole2.h> 
#include <stdio.h> 
#include <conio.h> 
#include "StatusX.h" 
 
// Function declarations 
inline void TESTHR(HRESULT x) {if FAILED(x) _com_issue_error(x);}; 
void StatusX(void); 
void PrintProviderError(_ConnectionPtr pConnection); 
void PrintComError(_com_error &e); 
 
/////////////////////////////////////////////// 
// // 
// Main Function // 
// // 
/////////////////////////////////////////////// 
 
void main() 
{ 
 if(FAILED(CoInitialize(NULL))) 
 return; 
 
 StatusX(); 
 
 ::CoUninitialize(); 
} 
 
/////////////////////////////////////////////// 
// // 
// StatusX Function // 
// // 
/////////////////////////////////////////////// 
void StatusX(void) 
{ 
 HRESULT hr = S_OK; 
 
 // Define string variables. 
 _bstr_t strCnn("Provider='sqloledb';Data Source='MySqlServer';" 
 "Initial Catalog='pubs';Integrated Security='SSPI';"); 
 
 // Define ADO object pointers. 
 // Initialize pointers on define. 
 // These are in the ADODB:: namespace. 
 IADORecordBinding *picRs = NULL; // Interface Pointer Declared 
 CTitleRs titlers; // C++ Class Object 
 _RecordsetPtr pRstTitles = NULL; 
 LPSTR p_TempStr = NULL; 
 
 try 
 { 
 // Open recordset for batch update 
 TESTHR(hr = pRstTitles.CreateInstance(__uuidof(Recordset))); 
 pRstTitles->CursorType = adOpenKeyset; 
 pRstTitles->LockType = adLockBatchOptimistic; 
 pRstTitles->Open ("titles", strCnn, 
 adOpenKeyset, adLockBatchOptimistic, adCmdTable); 
 
 // Open an IADORecordBinding interface pointer which 
 // we will use for binding Recordset to a class. 
 TESTHR(hr = pRstTitles->QueryInterface( 
 __uuidof(IADORecordBinding),(LPVOID*)&picRs)); 
 
 // Bind the Recordset to a C++ class here 
 TESTHR(hr = picRs->BindToRecordset(&titlers)); 
 
 p_TempStr = (LPSTR) malloc(sizeof(titlers.m_szt_Type)); 
 
 // Change the type of psychology titles. 
 while(!(pRstTitles->EndOfFile)) 
 { 
 // Set the final character of the destination string to NULL. 
 p_TempStr[sizeof(titlers.m_szt_Type)-1] = '\0'; 
 // The source string will get truncated if its length is 
 // longer than the length of the destination string minus one. 
 strncpy(p_TempStr,strtok(titlers.m_szt_Type," "), 
 sizeof(titlers.m_szt_Type)-1); 
 
 // Compare the type of psychology titles 
 if (!strcmp(p_TempStr,"psychology")) 
 { 
 // Copy "self_help" title field 
 pRstTitles->Fields->GetItem("type")->Value = 
 (_bstr_t) ("self_help"); 
 } 
 pRstTitles->MoveNext(); 
 } 
 
 // Display Title ID and status 
 pRstTitles->MoveFirst(); 
 while(!(pRstTitles->EndOfFile)) 
 { 
 if(pRstTitles->Status == adRecModified) 
 { 
 printf("%s - Modified\n",titlers.lt_Title_idStatus == 
 adFldOK ? titlers.m_szt_Title_id : "<NULL>"); 
 } 
 else 
 { 
 printf("%s\n",titlers.lt_Title_idStatus == adFldOK ? 
 titlers.m_szt_Title_id : "<NULL>"); 
 } 
 pRstTitles->MoveNext(); 
 } 
 } 
 catch (_com_error &e) 
 { 
 // Notify the user of errors if any. 
 // Pass a connection pointer accessed from the Recordset. 
 _variant_t vtConnect = pRstTitles->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; 
 } 
 } 
 
 // Deallocate the memory 
 if (p_TempStr) 
 free(p_TempStr); 
 
 if (pRstTitles) 
 if (pRstTitles->State == adStateOpen) 
 { 
 // Cancel the update because this is a demonstration. 
 pRstTitles->CancelBatch(adAffectAll); 
 pRstTitles->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; 
 
 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); 
 } 
 } 
} 
 
/////////////////////////////////////////////// 
// // 
// PrintComError Function // 
// // 
/////////////////////////////////////////////// 
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); 
} 
// EndStatusCpp 

StatusX.h

 
// BeginStatusH 
#include "icrsint.h" 
 
//This class extracts title_id and type from titles table. 
class CTitleRs : public CADORecordBinding 
{ 
 BEGIN_ADO_BINDING(CTitleRs) 
 // Column title_id is the 1st field in the table 
 ADO_VARIABLE_LENGTH_ENTRY2(1,adVarChar,m_szt_Title_id, 
 sizeof(m_szt_Title_id),lt_Title_idStatus,FALSE) 
 // Column type is the 3rd field in the table 
 ADO_VARIABLE_LENGTH_ENTRY2(3,adVarChar,m_szt_Type, 
 sizeof(m_szt_Type),lt_TypeStatus,TRUE) 
END_ADO_BINDING() 
 
public: 
 CHAR m_szt_Title_id[7]; 
 ULONG lt_Title_idStatus; 
 CHAR m_szt_Type[13]; 
 ULONG lt_TypeStatus; 
}; 
// EndStatusH