(转载)VB 查询Oracle中blob类型字段,并且把blob中的图片以流的方式显示在Image上

'模块代码
Private Declare Function CreateStreamOnHGlobal Lib "ole32" (ByVal hGlobal As Long, ByVal fDeleteOnRelease As Long, ppstm As Any) As Long
Private Declare Function OleLoadPicture Lib "olepro32" (pStream As Any, ByVal lSize As Long, ByVal fRunmode As Long, riid As Any, ppvObj As Any) As Long
Private Declare Function CLSIDFromString Lib "ole32" (ByVal lpsz As Any, pclsid As Any) As Long
Private Declare Function GlobalAlloc Lib "kernel32" (ByVal uFlags As Long, ByVal dwBytes As Long) As Long
Private Declare Function GlobalLock Lib "kernel32" (ByVal hMem As Long) As Long
Private Declare Function GlobalUnlock Lib "kernel32" (ByVal hMem As Long) As Long
Private Declare Sub MoveMemory Lib "kernel32" Alias "RtlMoveMemory" (pDest As Any, pSource As Any, ByVal dwLength As Long)
Private Declare Function GlobalFree Lib "kernel32" (ByVal hMem As Long) As Long Public Type GUID ' 16 bytes (128 bits)
'dwData1 As Long ' 4 bytes
'wData2 As Integer ' 2 bytes
'wData3 As Integer ' 2 bytes
abData4() As Byte ' 8 bytes, zero based
End Type Public Function PictureFromByteStream(B() As Byte) As IPicture
Dim hMem As Long
Dim lpMem As Long
Dim LowerBound As Long
Dim ByteCount As Long
Dim IID_IPicture As GUID
Dim istm As stdole.IUnknown LowerBound = LBound(B)
ByteCount = UBound(B) - LowerBound + hMem = GlobalAlloc(&H2, ByteCount) If hMem <> Then lpMem = GlobalLock(hMem) If lpMem <> Then MoveMemory ByVal lpMem, B(LowerBound), ByteCount GlobalUnlock hMem If CreateStreamOnHGlobal(hMem, , istm) = Then If CLSIDFromString(StrPtr("{7BF80980-BF32-101A-8BBB-00AA00300CAB}"), IID_IPicture) = Then OleLoadPicture ByVal ObjPtr(istm), ByteCount, , IID_IPicture, PictureFromByteStream End If End If End If End If End Function
Public Sub Combo1_Click()

Dim adoCnn As ADODB.Connection
Dim rstOra As ADODB.Recordset
Dim intI As Integer Set adoCnn = New ADODB.Connection
Set rstOra = New ADODB.Recordset adoCnn.ConnectionString = "Provider=OraOLEDB.Oracle;User ID=dzjc;password=zlkj;Data Source=dzjc_2005;" '读blob字段要用Provider=OraOLEDB.Oracle adoCnn.CursorLocation = adUseClient
adoCnn.Open rstOra.CursorLocation = adUseClient rstOra.ActiveConnection = adoCnn
rstOra.Open "SELECT zp FROM dzjc.dzjc_wfzp WHERE xh = '5'" 'Set Image1.DataSource = rstOra Set Image1.Picture = PictureFromByteStream(rstOra.Fields("zp").Value) End Sub
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