正在阅读：VC/VB 进行图像数据存储数据库心得VC/VB 进行图像数据存储数据库心得

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 Dim rs As ADODB.Recordset Set rs = New ADODB.Recordset DcnNWind.CursorLocation = adUseClient DcnNWind.Open "Provider=SQLOLEDB.1;Integrated Security=SSPI;Persist Security Info=False;Initial Catalog=CUSTOM;Data Source=SERVER" rs.CursorType = adOpenKeyset rs.LockType = adLockOptimistic rs.Open "CustomInfo", DcnNWind, , adCmdTable rs.Move (IndexNumber) Call FileToBlob(rs.Fields("Image"), FileName, FileLen(FileName)) rs.UpdateBatch adAffectCurrent End Sub Private Sub FileToBlob(fld As ADODB.Field, FileName As String, Optional ChunkSize As Long ) Dim fnum As Integer, bytesLeft As Long, bytes As Long Dim tmp() As Byte If (fld.Attributes And adFldLong) = 0 Then Err.Raise 1001, , "Field doesn't support the GetChunk method." End If fnum = FreeFile Open FileName For Binary As fnum bytesLeft = LOF(fnum) Do While bytesLeft bytes = bytesLeft If bytes > ChunkSize Then bytes = ChunkSize ReDim tmp(1 To bytes) As Byte Get #1, , tmp fld.AppendChunk tmp bytesLeft = bytesLeft - bytes Loop Close #fnum End Sub

Sub loadpic(IndexNumber As Long) Dim DcnNWind As New ADODB.Connection Dim rs As ADODB.Recordset Set rs = New ADODB.Recordset DcnNWind.CursorLocation = adUseClient DcnNWind.Open "Provider=SQLOLEDB.1;Integrated Security=SSI;Persist Security Info=False;Initial Catalog=CUSTOM;Data Source=SERVER" rs.CursorType = adOpenKeyset rs.LockType = adLockOptimistic rs.Open "CustomInfo", DcnNWind, , adCmdTable rs.Move (IndexNumber) Call BlobToFile(rs.Fields("Image"), "c:\windows\temp\tmp.bmp", rs.Fields("Image").ActualSize) End Sub Private Sub BlobToFile(fld As ADODB.Field, FileName As String, Optional ChunkSize As Long ) Dim fnum As Integer, bytesLeft As Long, bytes As Long Dim tmp() As Byte If (fld.Attributes And adFldLong) = 0 Then Err.Raise 1001, , "Field doesn't support the GetChunk method." End If If Dir$(FileName) <> "" Then Kill FileName fnum = FreeFile Open FileName For Binary As fnum bytesLeft = fld.ActualSize Do While bytesLeft bytes = bytesLeft If bytes > ChunkSize Then bytes = ChunkSize tmp = fld.GetChunk(bytes) Put #fnum, , tmp bytesLeft = bytesLeft - bytes Loop Close #fnum End Sub