VB窗体特效实现：渐现、展开、API动态与图形化

1、窗体的渐现渐隐

●特效描述：窗体从一个点逐渐变大，单击窗体后逐渐变小消失。 
●实现原理：在窗体加载时，先在屏幕上画一系列有效到大的矩形，直到矩形的大小与窗体的大小相同。这样，看上去窗体就好像是从小变大一样。卸载时，原理也相似，只是过程相反罢了。 
●实现方法：新建一个窗体，输入以下代码： 
●源代码： 
Private Declare Function GetWindowRect Lib "user32" (ByVal hwnd As Long, lpRect As RECT) As Long 
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 Rectangle Lib "gdi32" (ByVal hdc As Long, ByVal X1 As Long, ByVal Y1 As Long, ByVal X2 As Long, ByVal Y2 As Long) As Long 
Private Declare Function CreateSolidBrush Lib "gdi32" (ByVal crColor As Long) As Long 
Private Declare Function SelectObject Lib "gdi32" (ByVal hdc As Long, ByVal hObject As Long) As Long 
Private Declare Function DeleteObject Lib "gdi32" (ByVal hObject As Long) As Long 
Private Type RECT 
Left As Long 
Top As Long 
Right As Long 
Bottom As Long 
End Type 
Private Sub Form_Load() 
'窗体装载时 
Dim myRect As RECT 
Dim formWidth%, formHeight%, i%, X%, Y%, Cx%, Cy% 
Dim Screen As Long 
Dim Brush As Long 
GetWindowRect Form1.hwnd, myRect '获得窗体四角的坐标 
'计算窗体的高与宽 
formWidth = myRect.Right - myRect.Left 
formHeight = myRect.Bottom - myRect.Top 
Screen = GetDC(0) 

'创建实色画刷 
Brush = CreateSolidBrush(Form1.BackColor) 
'将创建的画刷选入设备描述表中 
SelectObject Screen, Brush 
'从小到大依次绘制矩形，直到与窗体大小相同为止 
For i = 1 To 3000 
Cx = formWidth * (i / 3000) 
Cy = formHeight * (i / 3000) 
X = myRect.Left + (formWidth - Cx) / 2 
Y = myRect.Top + (formHeight - Cy) / 2 
Rectangle Screen, X, Y, X + Cx, Y + Cy 
Next i 
'释放 
X = ReleaseDC(0, Screen) 
'从内存中删除创建的画刷 
DeleteObject (Brush) 
End Sub 
Private Sub form_unload(Cancel As Integer) 
Dim myRect As RECT 
Dim formWidth%, formHeight%, i%, X%, Y%, Cx%, Cy% 
Dim Screen As Long 
Dim Brush As Long 

GetWindowRect Form1.hwnd, myRect 
formWidth = (myRect.Right - myRect.Left) 
formHeight = myRect.Bottom - myRect.Top 
Screen = GetDC(0) 
Brush = CreateSolidBrush(Form1.BackColor) 

For i = 3000 To 1 Step -1