在许多Windows软件的安装程序中，时常可以看到以某种颜色由浅至深的渐变为背景的窗口。使用VB制作这类窗口的方法有不少，而通过调用API函数绘制渐变的窗口背景色，似乎是一种既简单又节省资源的方法。
首先，在module文件中加入下列声明语句：
Declare Function CreateSolidBrush
Lib"GDI"(ByVal _
crColor As Long) As Integer
Declare Function
FillRect Lib"USER"(ByVal hDC As _
Integer，lpRect As RECT，ByVal hBrush As
Integer)As Integer
Declare Function DeleteObject Lib"GDI"(ByVal
hObject _
As Integer)As Integer
Type RECT
left As
Integer
top As Integer
right As Integer
bottom As Integer
EndType
然后，在窗口的Paint事件中加入下列代码：
Private Sub
Form_Paint()
Dim Color As Integer
Dim hBrush As Integer
Dim
OldMode As Integer
Dim RetVal As Integer
Dim StepSize As Integer
Dim X As Integer
Dim FillArea As RECT
OldMode%=Me.ScaleMode
Me.ScaleMode=3
StepSize%=1+Me.ScaleHeight/80
Color%=255
FillArea.left=0
FillArea.right=Me.ScaleWidth
FillArea.top=0
FillArea.bottom=StepSize%
For X%=1 To 80
hBrush%=CreateSolidBrush (RGB(0,0,Color%))
RetVal%=FillRect(Me.hDC,FillArea,hBrush%)
RetVal%=DeleteObject(hBrush%)
Color%=Color%-4
If Color% $#@60; 0 Then Color%=0
FillArea.top=FillArea.bottom
FillArea.bottom=FillArea.bottom+StepSize%
Next
Me.ScaleMode=OldMode%
EndSub
按F5运行，就会出现一个以从上至下、由浅至深的渐变蓝色为背景的窗口。对上述代码稍加改动，便可制作出各种颜色和水平方向的渐变背景。
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