菜鸟的问题，请高手赐教！！急急急！！！

[wanghongfeng]

如何在picturebox控件中放置透明背景的图片？不能用image控件的呀！

[xxlroad]

'试验一下 下面的代码

’保存为 Form1.frm
VERSION 5.00
Begin VB.Form Form1
AutoRedraw = -1 'True
BackColor = &H80000000&
Caption = "Form1"
ClientHeight = 4965
ClientLeft = 60
ClientTop = 345
ClientWidth = 6150
LinkTopic = "Form1"
ScaleHeight = 4965
ScaleWidth = 6150
StartUpPosition = 3 'Windows Default
Begin VB.PictureBox Picture1
Height = 3135
Left = 600
Picture = "Form1.frx":0000
ScaleHeight = 3075
ScaleWidth = 2235
TabIndex = 1
Top = 240
Width = 2295
End
Begin VB.CommandButton Command1
Caption = "Command1"
Height = 855
Left = 4800
TabIndex = 0
Top = 3840
Width = 1095
End
End
Attribute VB_Name = "Form1"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit


Private Sub Command1_Click()
Dim R As RECT
With R
.Left = 0
.Top = 0
.Right = Picture1.ScaleWidth
.Bottom = Picture1.ScaleHeight
End With
TransparentBlt Form1.hdc, Form1.hdc, Picture1.hdc, R, 20, 20, vbWhite
Picture1.Visible = False
End Sub




’保存为 Module1.bas

Attribute VB_Name = "Module1"
Option Explicit
Public Type RECT
Left As Long
Top As Long
Right As Long
Bottom As Long
End Type

Public Declare Function BitBlt Lib "gdi32" (ByVal hDCDest As Long, ByVal XDest As Long, ByVal YDest As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hDCSrc As Long, ByVal XSrc As Long, ByVal YSrc As Long, ByVal dwRop As Long) As Long
Public Declare Function CreateBitmap Lib "gdi32" (ByVal nWidth As Long, ByVal nHeight As Long, ByVal nPlanes As Long, ByVal nBitCount As Long, lpBits As Any) As Long
Public Declare Function SetBkColor Lib "gdi32" _
(ByVal hdc As Long, ByVal crColor As Long) As Long
Public Declare Function SelectObject Lib "gdi32" _
(ByVal hdc As Long, ByVal hObject As Long) As Long
Public Declare Function CreateCompatibleBitmap Lib "gdi32" _
(ByVal hdc As Long, ByVal nWidth As Long, ByVal nHeight As Long) As Long
Public Declare Function CreateCompatibleDC Lib "gdi32" _
(ByVal hdc As Long) As Long
Public Declare Function DeleteDC Lib "gdi32" _
(ByVal hdc As Long) As Long
Public Declare Function DeleteObject Lib "gdi32" _
(ByVal hObject As Long) As Long

Public Sub TransparentBlt(OutDstDC As Long, DstDC As Long, SrcDC As Long, SrcRect As RECT, DstX As Integer, DstY As Integer, TransColor As Long)
'DstDC- Device context into which image must be drawn transparently
'OutDstDC- Device context into image is actually drawn, even though
'it is made transparent in terms of DstDC
'Src- Device context of source to be made transparent in color TransColor

'SrcRect- Rectangular region within SrcDC to be made transparent in terms of
'DstDC, and drawn to OutDstDC
'DstX, DstY - Coordinates in OutDstDC (and DstDC) where the transparent bitmap must go
'In most cases, OutDstDC and DstDC will be the same
Dim nRet As Long, W As Integer, H As Integer
Dim MonoMaskDC As Long, hMonoMask As Long
Dim MonoInvDC As Long, hMonoInv As Long
Dim ResultDstDC As Long, hResultDst As Long
Dim ResultSrcDC As Long, hResultSrc As Long
Dim hPrevMask As Long, hPrevInv As Long
Dim hPrevSrc As Long, hPrevDst As Long
W = SrcRect.Right - SrcRect.Left + 1
H = SrcRect.Bottom - SrcRect.Top + 1
'create monochrome mask and inverse masks
MonoMaskDC = CreateCompatibleDC(DstDC)
MonoInvDC = CreateCompatibleDC(DstDC)
hMonoMask = CreateBitmap(W, H, 1, 1, ByVal 0&)
hMonoInv = CreateBitmap(W, H, 1, 1, ByVal 0&)
hPrevMask = SelectObject(MonoMaskDC, hMonoMask)
hPrevInv = SelectObject(MonoInvDC, hMonoInv)
'create keeper DCs and bitmaps
ResultDstDC = CreateCompatibleDC(DstDC)
ResultSrcDC = CreateCompatibleDC(DstDC)
hResultDst = CreateCompatibleBitmap(DstDC, W, H)
hResultSrc = CreateCompatibleBitmap(DstDC, W, H)
hPrevDst = SelectObject(ResultDstDC, hResultDst)
hPrevSrc = SelectObject(ResultSrcDC, hResultSrc)
'copy src to monochrome mask
Dim OldBC As Long
OldBC = SetBkColor(SrcDC, TransColor)
nRet = BitBlt(MonoMaskDC, 0, 0, W, H, SrcDC, SrcRect.Left, SrcRect.Top, vbSrcCopy)
TransColor = SetBkColor(SrcDC, OldBC)
'create inverse of mask
nRet = BitBlt(MonoInvDC, 0, 0, W, H, MonoMaskDC, 0, 0, vbNotSrcCopy)
'get background
nRet = BitBlt(ResultDstDC, 0, 0, W, H, DstDC, DstX, DstY, vbSrcCopy)
'AND with Monochrome mask
nRet = BitBlt(ResultDstDC, 0, 0, W, H, MonoMaskDC, 0, 0, vbSrcAnd)
'get overlapper
nRet = BitBlt(ResultSrcDC, 0, 0, W, H, SrcDC, SrcRect.Left, SrcRect.Top, vbSrcCopy)
'AND with inverse monochrome mask
nRet = BitBlt(ResultSrcDC, 0, 0, W, H, MonoInvDC, 0, 0, vbSrcAnd)
'XOR these two
nRet = BitBlt(ResultDstDC, 0, 0, W, H, ResultSrcDC, 0, 0, vbSrcInvert)
'output results
nRet = BitBlt(OutDstDC, DstX, DstY, W, H, ResultDstDC, 0, 0, vbSrcCopy)
'clean up
hMonoMask = SelectObject(MonoMaskDC, hPrevMask)
DeleteObject hMonoMask
hMonoInv = SelectObject(MonoInvDC, hPrevInv)
DeleteObject hMonoInv
hResultDst = SelectObject(ResultDstDC, hPrevDst)
DeleteObject hResultDst
hResultSrc = SelectObject(ResultSrcDC, hPrevSrc)
DeleteObject hResultSrc
DeleteDC MonoMaskDC
DeleteDC MonoInvDC
DeleteDC ResultDstDC
DeleteDC ResultSrcDC
End Sub