屏幕对象捉图怎么实现？？？？

[Dnce]

就是象一般捉图软件那样，mouse在移动就得到句柄矩形。然后在上面画个矩形？？点击就捉下了？？

[goodname008]

大致思路：
GetCursorPos 获得鼠标位置
WindowFromPoint 获得鼠标位置下的窗口句柄
GetWindowRect 获得窗口矩形位置
然后用下面的函数抓图。

[goodname008]

Option Explicit
Private Declare Function CreateDC Lib "gdi32.dll" Alias "CreateDCA" (ByVal lpDriverName As String, ByVal lpDeviceName As String, ByVal lpOutput As String, lpInitData As Any) As Long
Private Declare Function CreateCompatibleDC Lib "gdi32.dll" (ByVal hdc As Long) As Long
Private Declare Function CreateCompatibleBitmap Lib "gdi32.dll" (ByVal hdc As Long, ByVal nWidth As Long, ByVal nHeight As Long) As Long
Private Declare Function SelectObject Lib "gdi32.dll" (ByVal hdc As Long, ByVal hObject As Long) As Long
Private Declare Function BitBlt Lib "gdi32.dll" (ByVal hDestDC As Long, ByVal x As Long, ByVal y As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hSrcDC As Long, ByVal xSrc As Long, ByVal ySrc As Long, ByVal dwRop As Long) As Long
Private Declare Function OpenClipboard Lib "user32.dll" (ByVal hwnd As Long) As Long
Private Declare Function EmptyClipboard Lib "user32.dll" () As Long
Private Declare Function CloseClipboard Lib "user32.dll" () As Long
Private Declare Function SetClipboardData Lib "user32.dll" (ByVal wFormat As Long, ByVal hMem As Long) As Long
Private Declare Function DeleteDC Lib "gdi32.dll" (ByVal hdc As Long) As Long
Private Declare Function ReleaseDC Lib "user32.dll" (ByVal hwnd As Long, ByVal hdc As Long) As Long

Private Sub Command1_Click()
ScreenCapture 0, 0, 100, 100
Picture1.Picture = Clipboard.GetData()
End Sub

' 将屏幕中指定区域的图像复制到剪贴板
' 例: ScreenCapture 0, 0, Screen.Width / 15, Screen.Height / 15
' object.Picture = Clipboard.GetData()
Function ScreenCapture(ByVal Left As Integer, ByVal Top As Integer, ByVal Right As Integer, ByVal Bottom As Integer) As Boolean
Dim rWidth As Integer, rHeight As Integer
Dim SourceDC As Long, DestDC As Long, bHandle As Long, dHandle As Long, wnd As Long
rWidth = Right - Left
rHeight = Bottom - Top
SourceDC = CreateDC("DISPLAY", 0, 0, 0)
DestDC = CreateCompatibleDC(SourceDC)
bHandle = CreateCompatibleBitmap(SourceDC, rWidth, rHeight)
SelectObject DestDC, bHandle
BitBlt DestDC, 0, 0, rWidth, rHeight, SourceDC, Left, Top, &HCC0020
wnd = Screen.ActiveForm.hwnd
OpenClipboard wnd
EmptyClipboard
ScreenCapture = SetClipboardData(2, bHandle)
CloseClipboard
DeleteDC DestDC
ReleaseDC dHandle, SourceDC
End Function

[yinsalon]

Use QQ can do it
correct?

[goodname008]

QQ的那个功能倒是不错。 :)

[Dnce]

谢谢： goodname008
具体实现就不一样了。

我的问题关键是在什么地方画矩形？？如何才能使画出的矩形能正确地清掉。
1.直接在屏幕上画，好象不行，由于mouse移动工具条按钮重画，所以矩形不能清掉(xor)。
再个点击时也想应了系统的单击事件（比如捉按钮，它的单击也响应了）。
2.把整个屏幕copy到窗体上（最大化），mouse在窗体上移动画矩形。（一般的捉图软件好象 都是这样做的）。但在窗体上如何得用GetCursorPos，GetWindowRect，得到我的对象矩形呢？？

[BlueBeer]

楼上的第二个方法完全可行，而且连API都省掉了

复制屏幕到窗体，窗体全屏显示，在mousedown时记下鼠标在窗体的位置（其实也就是屏幕上的位置），然后拖到鼠标，再到mouseup时再记下一个鼠标位置，矩形不就有了嘛，然后用paintpicture复制矩形内的图像就可以了

[BlueBeer]

晕哦，我话刚说完，人家帖子都结了：）
也罢，为人民服务了：）