VC/VB 进行图像数据存储数据库心得

CFile imagefile;
if(0 == imagefile.Open("d:\\user\\bmp.bmp",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);
}

_RecordsetPtr pRs = NULL;
_ConnectionPtr pConnection = NULL;
_variant_t varChunk;
HRESULT hr;
VARIANT varBLOB;
_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);
pRs.CreateInstance(__uuidof(Recordset));
pRs->Open("CustomInfo",_variant_t((IDispatch *) pConnection,true),adOpenKeyset,adLockOptimistic,adCmdTable);
//read data
long lDataLength = pRs->Fields->GetItem("Image")->ActualSize;
varBLOB = pRs->GetFields()->GetItem("Image")->GetChunk(lDataLength);
if(varBLOB.vt == (VT_ARRAY | VT_UI1))
{
BYTE *pBuf = NULL;
pBuf = (BYTE*)GlobalAlloc(GMEM_FIXED,lDataLength);
SafeArrayAccessData(varBLOB.parray,(void **)pBuf);
//Build a File in Windows Temp Directory
char tmpPath[_MAX_PATH+1];
GetTempPath(_MAX_PATH,tmpPath);
CString strFileName = "temp.bmp";
strFileName = tmpPath+strFileName;

CFile outFile(strFileName,Cfile::modeCreate|Cfile::modeWrite);
LPSTR buffer = (LPSTR)GlobalLock((HGLOBAL)pBuf);
outFile.WriteHuge(buffer,lDataLength);
GlobalUnlock((HGLOBAL)pBuf);
outFile.Close();
SafeArrayUnaccessData (varBLOB.parray);
}

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);
}

Sub savepic(FileName As String, IndexNumber As Long)
Dim DcnNWind As New ADODB.Connection
D