本文转自:http://www.cnblogs.com/dskin/p/4606293.html
做过.NET Winform窗体美化的人应该都很熟悉UpdateLayeredWindow吧,UpdateLayeredWindow可以实现窗体的任意透明,效果很好,不会有毛边。不过使用这个API之后,会有一个问题就是无法使用普通控件,而且没有Paint消息。为了解决这个问题,有两种方法。
一、使用双层窗体,底层窗体使用UpdateLayeredWindow作为背景,上层窗体用普通窗体,并且可以使用TransparencyKey或者Region来实现去除不需要的窗体内容,让上层窗体能看到底层的窗体。
二、直接单层窗体,使用控件的DrawToBitmap把控件图像绘制到UpdateLayeredWindow的窗体上,这样就可以看到普通控件了。不过这个也有问题:1.控件内容不能自动更新 2.效率低,很多控件使用DrawToBitmap绘制出的图像不完整,甚至绘制不出图像。比如TextBox无法显示光标,WebBrowser无法显示内容。
三、采用DirectUI技术,重写所有基础控件。效果最好,不过工作量巨大。
使用UpdateLayeredWindow时,一般是需要对Bitmap缓存起来,通过设置剪辑区域,局部重绘来提高效率。另外还可以异步重绘,模拟Winform的失效到重绘。
有些人会说为什么不直接用WPF啊,Wpf和Winform各有优缺点,适应不同的场合。Winform相对于使用更简单一些,系统要求更低。当然需要看人的习惯了和擅长的。
UpdateLayeredWindow 基本使用方法:
重写窗体的 CreateParams 属性
1
2
3
4
5
6
7
8
9
|
protected
override
CreateParams CreateParams
{
get
{
CreateParams cp =
base
.CreateParams;
cp.ExStyle |= 0x00080000 ;
// WS_EX_LAYERED 扩展样式
return
cp;
}
}
|
API调用:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
|
public
void
SetBitmap(Bitmap bitmap,
byte
opacity)
{
if
(bitmap.PixelFormat != PixelFormat.Format32bppArgb)
throw
new
ApplicationException(
"位图必须是32位包含alpha 通道"
);
IntPtr screenDc = Win32.GetDC(IntPtr.Zero);
IntPtr memDc = Win32.CreateCompatibleDC(screenDc);
IntPtr hBitmap = IntPtr.Zero;
IntPtr oldBitmap = IntPtr.Zero;
try
{
hBitmap = bitmap.GetHbitmap(Color.FromArgb( 0 ));
// 创建GDI位图句柄,效率较低
oldBitmap = Win32.SelectObject(memDc, hBitmap);
Win32.Size size =
new
Win32.Size(bitmap.Width, bitmap.Height);
Win32.Point pointSource =
new
Win32.Point( 0 , 0 );
Win32.Point topPos =
new
Win32.Point(Left, Top);
Win32.BLENDFUNCTION blend =
new
Win32.BLENDFUNCTION();
blend.BlendOp = Win32.AC_SRC_OVER;
blend.BlendFlags = 0 ;
blend.SourceConstantAlpha = opacity;
blend.AlphaFormat = Win32.AC_SRC_ALPHA;
Win32.UpdateLayeredWindow(Handle, screenDc,
ref
topPos,
ref
size, memDc,
ref
pointSource, 0 ,
ref
blend, Win32.ULW_ALPHA);
}
finally
{
Win32.ReleaseDC(IntPtr.Zero, screenDc);
if
(hBitmap != IntPtr.Zero)
{
Win32.SelectObject(memDc, oldBitmap);
Win32.DeleteObject(hBitmap);
}
Win32.DeleteDC(memDc);
}
}
|
API声明:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
class
Win32
{
public
enum
Bool
{
False = 0 ,
True
} ;
[StructLayout(LayoutKind.Sequential)]
public
struct
Point
{
public
Int32 x;
public
Int32 y;
public
Point(Int32 x, Int32 y)
{
this
.x = x;
this
.y = y; }
}
[StructLayout(LayoutKind.Sequential)]
public
struct
Size
{
public
Int32 cx;
public
Int32 cy;
public
Size(Int32 cx, Int32 cy)
{
this
.cx = cx;
this
.cy = cy; }
}
[StructLayout(LayoutKind.Sequential, Pack = 1 )]
struct
ARGB
{
public
byte
Blue;
public
byte
Green;
public
byte
Red;
public
byte
Alpha;
}
[StructLayout(LayoutKind.Sequential, Pack = 1 )]
public
struct
BLENDFUNCTION
{
public
byte
BlendOp;
public
byte
BlendFlags;
public
byte
SourceConstantAlpha;
public
byte
AlphaFormat;
}
public
const
Int32 ULW_COLORKEY = 0x00000001 ;
public
const
Int32 ULW_ALPHA = 0x00000002 ;
public
const
Int32 ULW_OPAQUE = 0x00000004 ;
public
const
byte
AC_SRC_OVER = 0x00 ;
public
const
byte
AC_SRC_ALPHA = 0x01 ;
[DllImport(
" user32.dll "
, ExactSpelling =
true
, SetLastError =
true
)]
public
static
extern
Bool UpdateLayeredWindow(IntPtr hwnd, IntPtr hdcDst,
ref
Point pptDst,
ref
Size psize, IntPtr hdcSrc,
ref
Point pprSrc, Int32 crKey,
ref
BLENDFUNCTION pblend, Int32 dwFlags);
[DllImport(
" user32.dll "
, ExactSpelling =
true
, SetLastError =
true
)]
public
static
extern
IntPtr GetDC(IntPtr hWnd);
[DllImport(
" user32.dll "
, ExactSpelling =
true
)]
public
static
extern
int
ReleaseDC(IntPtr hWnd, IntPtr hDC);
[DllImport(
" gdi32.dll "
, ExactSpelling =
true
, SetLastError =
true
)]
public
static
extern
IntPtr CreateCompatibleDC(IntPtr hDC);
[DllImport(
" gdi32.dll "
, ExactSpelling =
true
, SetLastError =
true
)]
public
static
extern
Bool DeleteDC(IntPtr hdc);
[DllImport(
" gdi32.dll "
, ExactSpelling =
true
)]
public
static
extern
IntPtr SelectObject(IntPtr hDC, IntPtr hObject);
[DllImport(
" gdi32.dll "
, ExactSpelling =
true
, SetLastError =
true
)]
public
static
extern
Bool DeleteObject(IntPtr hObject);
[DllImport(
" user32.dll "
, EntryPoint =
" SendMessage "
)]
public
static
extern
int
SendMessage(
int
hWnd,
int
wMsg,
int
wParam,
int
lParam);
[DllImport(
" user32.dll "
, EntryPoint =
" ReleaseCapture "
)]
public
static
extern
int
ReleaseCapture();
public
const
int
WM_SysCommand = 0x0112 ;
public
const
int
SC_MOVE = 0xF012 ;
public
const
int
SC_MAXIMIZE = 61488 ;
public
const
int
SC_MINIMIZE = 61472 ;
}
|
需要呈现图像的时候调用 SetBitmap 方法。只要优化好,呈现效率比普通的Paint重绘方式高很多,并且不卡不闪烁,支持任意透明。
下面是自己开发出来的效果:
这个是用OpenGL绘制的
推荐一款C#界面库:DSkin界面库(Winform平台首个DirectUI界面库) http://d.cskin.net