利用VB产生屏幕变暗的效果. (转)[@more@]
利用VB产生屏幕变暗的效果.想利用VB 实现屏幕变暗的效果（向关闭Win95时的效果），只要按下面的步骤来做
1、在Form1中加入两个Comman utton和一个PictureBox.
2、在Form1的代码窗口中添加以下代码：
Private Type RECT
Left As Long
Top As Long
Right As Long
Bottom As Long
End Type
Private Declare Function GetDC Lib "user32" (ByVal hwnd As Long) As Long
Private Declare Function ReleaseDC Lib "user32" (ByVal hwnd As Long, ByVal hdc As Long) As
Long
Private Declare Function CreatePatternBrush Lib "gdi32" (ByVal hBitmap As Long) As Long
Private Declare Function PatBlt Lib "gdi32" (ByVal hdc As Long, ByVal x As Long, ByVal y As
Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal dwRop As Long) As Long
Private Declare Function Delete Lib "gdi32" (ByVal hObject As Long) As Long
Private 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
Private Declare Function Object Lib "gdi32" (ByVal hdc As Long, ByVal hObject As Long)
As Long
Private Declare Function InvalidateRect Lib "user32" (ByVal hwnd As Long, ByVal lpRect As
Long, ByVal bErase As Long) As Long
Private bybits(1 To 16) As Byte
Private hBitmap As Long, hBrush As Long
Private hDesktopWnd As Long
Private Sub Command1_Click()
Dim rop As Long, res As Long
Dim hdc5 As Long, width5 As Long, height5 As Long
hdc5 = GetDC(0)
width5 = Screen.Width Screen.TwipsPerPixelX
height5 = Screen.Height Screen.TwipsPerPixelY
rop = &HA000C9
Call SelectObject(hdc5, hBrush)
res = PatBlt(hdc5, 0, 0, width5, height5, rop)
Call DeleteObject(hBrush)
res = ReleaseDC(0, hdc5)
End Sub
Private Sub Command2_Click()
Dim aa As Long
aa = InvalidateRect(0, 0, 1)
End Sub
Private Sub Form_Load()
Dim ary
Dim i As Long
ary = Array(&H55, &H0, &HAA, &H0, _
&H55, &H0, &HAA, &H0, _
&H55, &H0, &HAA, &H0, _
&H55, &H0, &HAA, &H0)
For i = 1 To 16
bybits(i) = ary(i - 1)
Next i
hBitmap = CreateBitmap(8, 8, 1, 1, bybits(1))
hBrush = CreatePatternBrush(hBitmap)
Picture1.ForeColor = RGB(0, 0, 0)
Picture1.BackColor = RGB(255, 255, 255)
Picture1.ScaleMode = 3
End Sub
运行 ，按Command1就可以使屏幕暗下来，按Command2恢复。
来自 “ ITPUB博客 ” ，链接：http://blog.itpub.net/10748419/viewspace-983509/，如需转载，请注明出处，否则将追究法律责任。