关于图片在数据库的存取问题

Question

麻烦给我一份ADO的例子，谢谢！！！
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Answer 1

ADO的例子我要，谢谢，加50分。

Answer 2

CFile imagefile;
  if(0 == imagefile.Open(文件名,CFile::modeRead))
     return;
  _RecordsetPtr pRs = NULL;             
  _ConnectionPtr pConnection = NULL;
  _variant_t varChunk;
  HRESULT hr;
  BYTE* pbuf;
  long nLength = imagefile.GetLength();
  pbuf = new BYTE[nLength+2];
  if(pbuf == NULL)
     return;                             //allocate memory error;
  imagefile.Read(pbuf,nLength);          //read the file into memory  BYTE *pBufEx;
  pBufEx = pbuf;
  //build a SAFFERRAY
  SAFEARRAY* psa;
  SAFEARRAYBOUND rgsabound[1];
  rgsabound[0].lLbound = 0;
  rgsabound[0].cElements = nLength;
  psa = SafeArrayCreate(VT_UI1, 1, rgsabound);  for (long i = 0; i < nLength; i++)
       SafeArrayPutElement (psa, &i, pBufEx++);
  VARIANT varBLOB;
  varBLOB.vt = VT_ARRAY | VT_UI1;
  varBLOB.parray = psa;  _bstr_t strCnn("Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=CUSTOM;Data Source=SERVER");   
    try
    {
        //Open a connection
        pConnection.CreateInstance(__uuidof(Connection));
        hr = pConnection->Open(strCnn,"","",NULL);   //Connect a DataBase
        pRs.CreateInstance(__uuidof(Recordset));
        pRs->Open("CustomInfo",_variant_t((IDispatch *) pConnection,true),adOpenKeyset,adLockOptimistic,adCmdTable);  //Open a Table
 
//      pRs->AddNew();       
        pRs->Fields->GetItem("Image")->AppendChunk(varBLOB);       
        pRs->Update();
        pRs->Close();
        pConnection->Close();
 }
    catch(_com_error &e)
    {
        // Notify the user of errors if any.
        _bstr_t bstrSource(e.Source());
        _bstr_t bstrDescription(e.Description());
        CString sError;
        sError.Format("Source : %s \n Description : %s\n",(LPCSTR)bstrSource,(LPCSTR)bstrDescription);
        AfxMessageBox(sError);    
 }　

Answer 3

请问上面这个例子要改成ODBC怎么改？

Answer 4

我只有一個ODBC的例子,但不是操作圖片.

Answer 5

;
  
      _bstr_t  strCnn("Provider=SQLOLEDB.1;Integrated  Security=SSPI;Persist  Security  Info=False;Initial  Catalog=CUSTOM;Data  Source=SERVER");      
          try
          {
                  //Open  a  connection
                  pConnection.CreateInstance(__uuidof(Connection));
                  hr  =  pConnection->  Open(strCnn,"","",NULL);      //Connect  a  DataBase
                  pRs.CreateInstance(__uuidof(Recordset));
                  pRs->  Open("CustomInfo",_variant_t((IDispatch  *)  pConnection,true),adOpenKeyset,adLockOptimistic,adCmdTable);    //Open  a  Table
    
  //            pRs->  AddNew();              
                  pRs->  Fields->  GetItem("Image")->  AppendChunk(varBLOB);              
                  pRs->  Update();
                  pRs->  Close();
                  pConnection->  Close();
    }
          catch(_com_error  &  e)
          {
                  //  Notify  the  user  of  errors  if  any.
                  _bstr_t  bstrSource(e.Source());
                  _bstr_t  bstrDescription(e.Description());
                  CString  sError;
                  sError.Format("Source  :  %s  \n  Description  :  %s\n",(LPCSTR)bstrSource,(LPCSTR)bstrDescription);
                  AfxMessageBox(sError);        
改成ODBC怎么改？

Answer 6

;
  
      _bstr_t  strCnn("Provider=SQLOLEDB.1;Integrated  Security=SSPI;Persist  Security  Info=False;Initial  Catalog=CUSTOM;Data  Source=SERVER");      
          try
          {
                  //Open  a  connection
                  pConnection.CreateInstance(__uuidof(Connection));
                  hr  =  pConnection->  Open(strCnn,"","",NULL);      //Connect  a  DataBase
                  pRs.CreateInstance(__uuidof(Recordset));
                  pRs->  Open("CustomInfo",_variant_t((IDispatch  *)  pConnection,true),adOpenKeyset,adLockOptimistic,adCmdTable);    //Open  a  Table
    
  //            pRs->  AddNew();              
                  pRs->  Fields->  GetItem("Image")->  AppendChunk(varBLOB);              
                  pRs->  Update();
                  pRs->  Close();
                  pConnection->  Close();
    }
          catch(_com_error  &  e)
          {
                  //  Notify  the  user  of  errors  if  any.
                  _bstr_t  bstrSource(e.Source());
                  _bstr_t  bstrDescription(e.Description());
                  CString  sError;
                  sError.Format("Source  :  %s  \n  Description  :  %s\n",(LPCSTR)bstrSource,(LPCSTR)bstrDescription);
                  AfxMessageBox(sError);        
    改成ODBC怎么改？

Answer 7

*****ODBC API******SQLHENV henv;
SQLHDBC hdbc;
SQLHSTMT hstmt;
SQLRETURN rtcode;//分配環境句柄
rtcode = SQLAllocHandle(SQL_HANDLE_ENV,SQL_NULL_HANDLE,&henv);
if(rtcode == SQL_SUCCESS || rtcode == SQL_SUCCESS_WITH_INFO)
{
    //設置環境屬性(ODBC版本號)
    rtcode = SQLSetEnvAttr(henv,SQL_ATTR_ODBC_VERSION,(void*)SQL_OV_ODBC3,0);
    if(rtcode == SQL_SUCCESS || rtcode == SQL_SUCCESS_WITH_INFO)
    {
         //分配連接句柄
         rtcode = SQLAllocHandle( SQL_HANDLE_DBC, henv, &hdbc);
         if(rtcode == SQL_SUCCESS || rtcode == SQL_SUCCESS_WITH_INFO)
         {     //設置連接屬性(超時時間10s)
               SQLSetConnectAttr(hdbc,SQL_ATTR_LOGIN_TIMEOUT,(void*)10,0);       //連接數據源
LPTSTR lpstrDsn="Provider=SQLOLEDB;SERVER=服務器名;DATABASE=數據庫名;UID=用戶;PWD=口令;"
               rtcode = SQLConnect(hdbc,(SQLCHAR*)lpstrDsn,SQL_NTS,(SQLCHAR*)"",SQL_NTS,(SQLCHAR*)"",SQL_NTS);
               if(rtcode == SQL_SUCCESS || rtcode == SQL_SUCCESS_WITH_INFO)
               { //分配語句句柄
                  rtcode = SQLAllocHandle(SQL_HANDLE_STMT,hdbc,&hstmt);
                  if(rtcode == SQL_SUCCESS || rtcode == SQL_SUCCESS_WITH_INFO)
                  {
*********執行操作****************         //釋放語句句柄
         SQLFreeHandle(SQL_HANDLE_STMT,hstmt);
         //斷開連接
SQLDisconnect(hdbc);
         //釋放連接句柄
SQLFreeHandle(SQL_HANDLE_DBC,hdbc);
         //釋放環境句柄
SQLFreeHandle(SQL_HANDLE_ENV,henv);

Answer 8

直接執行:
SQLRETURN SQLExecDirect(執行的語句句柄,SQL語句,SQL語句緩沖區大小);
SQLChar SQLStatement ="SELECT * FROM TABLE";
SQLExecDirect(hstmt,&SQLStatement,SQL_NTS);

Answer 9

這是MSDN上的一個例子:include <windows.h>
#include <stdio.h>
#include <sql.h>
#include <sqlext.h>int main(int argc, char* argv[])
{
SQLCHAR* theDiagState = new SQLCHAR[50]; SQLINTEGER theNativeState;
SQLCHAR* theMessageText  = new SQLCHAR[255]; SQLSMALLINT iOutputNo; SQLHENV m_SQLEnvironment;
SQLHDBC m_SQLConnection;
SQLHSTMT m_SQLStatement; SQLRETURN iReturn;
DWORD returnValue = 0;
DWORD returnValue1 = 0;
long lBufLength = sizeof(returnValue);
long lBufLength1 = sizeof(returnValue1);
SQLCHAR  theNumeric2[50];
SQLINTEGER cbNumeric, cbNumeric2;
strcpy((char*)theNumeric2, "5.9"); //Connect
//Allocate Environment Handle
iReturn = SQLAllocHandle(SQL_HANDLE_ENV,SQL_NULL_HANDLE,&m_SQLEnvironment); //Set environment to ODBC_3
iReturn = SQLSetEnvAttr(m_SQLEnvironment,SQL_ATTR_ODBC_VERSION,(SQLPOINTER) SQL_OV_ODBC3,0); //Allocate connection handle
iReturn = SQLAllocHandle(SQL_HANDLE_DBC,m_SQLEnvironment,&m_SQLConnection); //Connect to the database.
//In this example we have used the following
//Pubs as the DSN name
//sa is the login name without a password
//CHANGE THE DSN NAME HERE along with the length of the DSN.

iReturn = SQLConnect(m_SQLConnection,(SQLCHAR*) "Pubs",4,(SQLCHAR*)"sa",2,(SQLCHAR*)"",0);
if (iReturn != SQL_ERROR)
{

//Run Query
//Allocate the statement handle
iReturn = SQLAllocHandle(SQL_HANDLE_STMT,m_SQLConnection,&m_SQLStatement);
//If you want to insert NULL data, the last parameter of SQLBindParameter should contain SQL_NULL_DATA
cbNumeric = SQL_NULL_DATA;
cbNumeric2 = SQL_NTS;
//Sending Null Data
iReturn = SQLBindParameter(m_SQLStatement,1,SQL_PARAM_INPUT,SQL_C_NUMERIC,SQL_NUMERIC,13,6,NULL,0,&cbNumeric);  
if (iReturn != SQL_SUCCESS)
{
SQLGetDiagRec(SQL_HANDLE_STMT,m_SQLStatement,1,theDiagState,&theNativeState,theMessageText,100,&iOutputNo);
}


//Sending nonNull Data
iReturn = SQLBindParameter(m_SQLStatement,2,SQL_PARAM_INPUT,SQL_C_CHAR,SQL_NUMERIC,13,6,theNumeric2,0,&cbNumeric2);  
if (iReturn != SQL_SUCCESS)
{
SQLGetDiagRec(SQL_HANDLE_STMT,m_SQLStatement,1,theDiagState,&theNativeState,theMessageText,100,&iOutputNo);
} //Execute the statement to insert a null and a non-null value to the table.
//CHANGE THE TABLE/COLUMN NAME HERE.
//In this case we have used a table called TestNULL in SQL Server 7.0 with two fields
//theNumber1 : Numeric Field that allows NULL data (Length =13, Precision = 28, Scale=6)
//theNumber2 : Numeric that does not allow NULL data (Length =13, Precision = 28, Scale=6)
iReturn = SQLExecDirect(m_SQLStatement,(SQLCHAR*) "Insert Into TestNull (theNumber1,theNumber2) Values (?,?)",SQL_NTS);
if (iReturn != SQL_SUCCESS)
{
SQLGetDiagRec(SQL_HANDLE_STMT,m_SQLStatement,1,theDiagState,&theNativeState,theMessageText,100,&iOutputNo);
} //DISCONNECT
iReturn = SQLFreeHandle(SQL_HANDLE_STMT,m_SQLStatement);
iReturn = SQLDisconnect(m_SQLConnection);
iReturn = SQLFreeHandle(SQL_HANDLE_DBC,m_SQLConnection);
iReturn = SQLFreeHandle(SQL_HANDLE_ENV,m_SQLEnvironment); m_SQLStatement = NULL;
m_SQLConnection = NULL;
m_SQLEnvironment = NULL;
}
else
{
//If it fails to connect theMessageText contains the reason for failure
SQLGetDiagRec(SQL_HANDLE_DBC,m_SQLConnection,1,theDiagState,&theNativeState,theMessageText,100,&iOutputNo); } delete theMessageText; 
delete theDiagState;
return 1;
}