VB6中从内存中（Byte 字节数组）加载图片

从内存（字节数组）加载图片

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)





Public Function PictureFromByteStream(b() As Byte) As IPicture
    Dim LowerBound As Long
    Dim ByteCount  As Long
    Dim hMem  As Long
    Dim lpMem  As Long
    Dim IID_IPicture(15)
    Dim istm As stdole.IUnknown

    On Error GoTo Err_Init
    If UBound(b, 1) < 0 Then
        Exit Function
    End If
    
    LowerBound = LBound(b)
    ByteCount = (UBound(b) - LowerBound) + 1
    hMem = GlobalAlloc(&H2, ByteCount)
    If hMem <> 0 Then
        lpMem = GlobalLock(hMem)
        If lpMem <> 0 Then
            MoveMemory ByVal lpMem, b(LowerBound), ByteCount
            Call GlobalUnlock(hMem)
            If CreateStreamOnHGlobal(hMem, 1, istm) = 0 Then
                If CLSIDFromString(StrPtr("{7BF80980-BF32-101A-8BBB-00AA00300CAB}"), IID_IPicture(0)) = 0 Then
                  Call OleLoadPicture(ByVal ObjPtr(istm), ByteCount, 0, IID_IPicture(0), PictureFromByteStream)
                End If
            End If
        End If
    End If
    
    Exit Function
    
Err_Init:
    If Err.Number = 9 Then
        'Uninitialized array
        MsgBox "您给函数提供的是空数组!"
    Else
        MsgBox Err.Number & " - " & Err.Description
    End If
End Function