所以我有以下代码:
#region Dropshadow
[DllImport("Gdi32.dll", EntryPoint = "CreateRoundRectRgn")]
private static extern IntPtr CreateRoundRectRgn
(
int nLeftRect,
int nTopRect,
int nRightRect,
int nBottomRect,
int nWidthEllipse,
int nHeightEllipse
);
[DllImport("dwmapi.dll")]
public static extern int DwmExtendFrameIntoClientArea(IntPtr hWnd, ref MARGINS pMarInset);
[DllImport("dwmapi.dll")]
public static extern int DwmSetWindowAttribute(IntPtr hwnd, int attr, ref int attrValue, int attrSize);
[DllImport("dwmapi.dll")]
public static extern int DwmIsCompositionEnabled(ref int pfEnabled);
private bool m_aeroEnabled;
public struct MARGINS
{
public int leftWidth;
public int rightWidth;
public int topHeight;
public int bottomHeight;
}
protected override CreateParams CreateParams {
get {
m_aeroEnabled = CheckAeroEnabled();
CreateParams cp = base.CreateParams;
if (!m_aeroEnabled) {
cp.ClassStyle |= 0x00020000;
}
return cp;
}
}
private bool CheckAeroEnabled()
{
if (Environment.OSVersion.Version.Major >= 6) {
int enabled = 0;
DwmIsCompositionEnabled(ref enabled);
return (enabled == 1) ? true : false;
}
return false;
}
protected override void WndProc(ref Message m)
{
switch (m.Msg) {
case 0x0085:
if (m_aeroEnabled) {
int v = 2;
DwmSetWindowAttribute(Handle, 2, ref v, 4);
MARGINS margins = new MARGINS() {
bottomHeight = 1,
leftWidth = 0,
rightWidth = 0,
topHeight = 0
};
DwmExtendFrameIntoClientArea(Handle, ref margins);
}
break;
default:
break;
}
base.WndProc(ref m);
}
#endregion
这使用 GDI 制作了一个 Dropshadow。 然而,唯一的问题是我必须让它在顶部保留 1 像素高度的边框(它可以是任何边缘,只是顶部在我的应用程序上最难注意到)。
这使得我的应用程序顶部出现一条线,这本质上降低了观看体验。
是否可以完全无边框地做到这一点?
(bottomHeight = 1代码就是它的全部内容。如果我将其设置为0,topHeight设置为1,则线条将位于底部。将它们全部设置为0,则根本不显示阴影。)
事实证明,这与我的填充有关,我需要在至少 1 个边缘上留出 1 个像素线为空,以便 Dropshadow 正常工作。我选择使用 Padding 来制作 1 像素线,并将顶部填充设置为 1。这会将线设置在顶部。 BottomHeight = 1 根本不重要。它就在那里,因为它要求其中至少有一个非 0。
这是一个使用 DWM 渲染其边框/阴影的 Form 类。
DWMWINDOWATTRIBUTE
,以及相关的策略 DWMNCRENDERINGPOLICY
,将其值设置为启用。DwmSetWindowAttribute()
设置属性,用 DwmExtendFrameIntoClientArea()
、DwmEnableBlurBehindWindow()
等等设置想要的效果。
所有需要的声明都在这里。
这是 Form 类(命名为“Borderless”,充满创意)。
我试图让它看起来像你已经发布的内容,以尽量减少“影响”。
该表单是一个标准的 WinForms 表单,带有
FormBorderStyle = None
。
public partial class Borderless : Form
{
public Borderless() => InitializeComponent();
protected override void OnHandleCreated(EventArgs e) {
base.OnHandleCreated(e);
WinApi.Dwm.DWMNCRENDERINGPOLICY Policy = WinApi.Dwm.DWMNCRENDERINGPOLICY.Enabled;
WinApi.Dwm.WindowSetAttribute(this.Handle, WinApi.Dwm.DWMWINDOWATTRIBUTE.NCRenderingPolicy, (int)Policy);
if (DWNCompositionEnabled()) { WinApi.Dwm.WindowBorderlessDropShadow(this.Handle, 2); }
//if (DWNCompositionEnabled()) { WinApi.Dwm.WindowEnableBlurBehind(this.Handle); }
//if (DWNCompositionEnabled()) { WinApi.Dwm.WindowSheetOfGlass(this.Handle); }
}
private bool DWNCompositionEnabled() => (Environment.OSVersion.Version.Major >= 6)
? WinApi.Dwm.IsCompositionEnabled()
: false;
protected override void WndProc(ref Message m)
{
switch (m.Msg)
{
case (int)WinApi.WinMessage.WM_DWMCOMPOSITIONCHANGED:
{
WinApi.Dwm.DWMNCRENDERINGPOLICY Policy = WinApi.Dwm.DWMNCRENDERINGPOLICY.Enabled;
WinApi.Dwm.WindowSetAttribute(this.Handle, WinApi.Dwm.DWMWINDOWATTRIBUTE.NCRenderingPolicy, (int)Policy);
WinApi.Dwm.WindowBorderlessDropShadow(this.Handle, 2);
m.Result = (IntPtr)0;
}
break;
default:
break;
}
base.WndProc(ref m);
}
}
这是一个部分类,因为
Winapi
类是一个扩展的类库。你可以改成你习惯的。我建议保留
Win32 API 声明的属性。[SuppressUnmanagedCodeSecurityAttribute]
public partial class WinApi
{
public enum WinMessage : int
{
WM_DWMCOMPOSITIONCHANGED = 0x031E, //The system will send a window the WM_DWMCOMPOSITIONCHANGED message to indicate that the availability of desktop composition has changed.
WM_DWMNCRENDERINGCHANGED = 0x031F, //WM_DWMNCRENDERINGCHANGED is called when the non-client area rendering status of a window has changed. Only windows that have set the flag DWM_BLURBEHIND.fTransitionOnMaximized to true will get this message.
WM_DWMCOLORIZATIONCOLORCHANGED = 0x0320, //Sent to all top-level windows when the colorization color has changed.
WM_DWMWINDOWMAXIMIZEDCHANGE = 0x0321 //WM_DWMWINDOWMAXIMIZEDCHANGE will let you know when a DWM composed window is maximized. You also have to register for this message as well. You'd have other windowd go opaque when this message is sent.
}
public class Dwm
public enum DWMWINDOWATTRIBUTE : uint
{
NCRenderingEnabled = 1, //Get only atttribute
NCRenderingPolicy, //Enable or disable non-client rendering
TransitionsForceDisabled,
AllowNCPaint,
CaptionButtonBounds,
NonClientRtlLayout,
ForceIconicRepresentation,
Flip3DPolicy,
ExtendedFrameBounds,
HasIconicBitmap,
DisallowPeek,
ExcludedFromPeek,
Cloak,
Cloaked,
FreezeRepresentation
}
public enum DWMNCRENDERINGPOLICY : uint
{
UseWindowStyle, // Enable/disable non-client rendering based on window style
Disabled, // Disabled non-client rendering; window style is ignored
Enabled, // Enabled non-client rendering; window style is ignored
};
// Values designating how Flip3D treats a given window.
enum DWMFLIP3DWINDOWPOLICY : uint
{
Default, // Hide or include the window in Flip3D based on window style and visibility.
ExcludeBelow, // Display the window under Flip3D and disabled.
ExcludeAbove, // Display the window above Flip3D and enabled.
};
public struct MARGINS
{
public int leftWidth;
public int rightWidth;
public int topHeight;
public int bottomHeight;
public MARGINS(int LeftWidth, int RightWidth, int TopHeight, int BottomHeight)
{
leftWidth = LeftWidth;
rightWidth = RightWidth;
topHeight = TopHeight;
bottomHeight = BottomHeight;
}
public void NoMargins()
{
leftWidth = 0;
rightWidth = 0;
topHeight = 0;
bottomHeight = 0;
}
public void SheetOfGlass()
{
leftWidth = -1;
rightWidth = -1;
topHeight = -1;
bottomHeight = -1;
}
}
[SuppressUnmanagedCodeSecurityAttribute]
internal static class SafeNativeMethods
{
//https://msdn.microsoft.com/en-us/library/windows/desktop/aa969508(v=vs.85).aspx
[DllImport("dwmapi.dll")]
internal static extern int DwmEnableBlurBehindWindow(IntPtr hwnd, ref DWM_BLURBEHIND blurBehind);
//https://msdn.microsoft.com/it-it/library/windows/desktop/aa969512(v=vs.85).aspx
[DllImport("dwmapi.dll")]
internal static extern int DwmExtendFrameIntoClientArea(IntPtr hWnd, ref MARGINS pMarInset);
//https://msdn.microsoft.com/en-us/library/windows/desktop/aa969515(v=vs.85).aspx
[DllImport("dwmapi.dll")]
internal static extern int DwmGetWindowAttribute(IntPtr hwnd, DWMWINDOWATTRIBUTE attr, ref int attrValue, int attrSize);
//https://msdn.microsoft.com/en-us/library/windows/desktop/aa969524(v=vs.85).aspx
[DllImport("dwmapi.dll")]
internal static extern int DwmSetWindowAttribute(IntPtr hwnd, DWMWINDOWATTRIBUTE attr, ref int attrValue, int attrSize);
[DllImport("dwmapi.dll")]
internal static extern int DwmIsCompositionEnabled(ref int pfEnabled);
}
public static bool IsCompositionEnabled()
{
int pfEnabled = 0;
int result = SafeNativeMethods.DwmIsCompositionEnabled(ref pfEnabled);
return pfEnabled == 1;
}
public static bool IsNonClientRenderingEnabled(IntPtr hWnd)
{
int gwaEnabled = 0;
int result = SafeNativeMethods.DwmGetWindowAttribute(hWnd, DWMWINDOWATTRIBUTE.NCRenderingEnabled, ref gwaEnabled, sizeof(int));
return gwaEnabled == 1;
}
public static bool WindowSetAttribute(IntPtr hWnd, DWMWINDOWATTRIBUTE Attribute, int AttributeValue)
{
int result = SafeNativeMethods.DwmSetWindowAttribute(hWnd, Attribute, ref AttributeValue, sizeof(int));
return result == 0;
}
public static bool WindowEnableBlurBehind(IntPtr hWnd)
{
//Create and populate the Blur Behind structure
DWM_BLURBEHIND Dwm_BB = new DWM_BLURBEHIND(true);
int result = SafeNativeMethods.DwmEnableBlurBehindWindow(hWnd, ref Dwm_BB);
return result == 0;
}
public static bool WindowExtendIntoClientArea(IntPtr hWnd, WinApi.Dwm.MARGINS Margins)
{
// Extend frame on the bottom of client area
int result = SafeNativeMethods.DwmExtendFrameIntoClientArea(hWnd, ref Margins);
return result == 0;
}
public static bool WindowBorderlessDropShadow(IntPtr hWnd, int ShadowSize)
{
MARGINS Margins = new MARGINS(0, ShadowSize, 0, ShadowSize);
int result = SafeNativeMethods.DwmExtendFrameIntoClientArea(hWnd, ref Margins);
return result == 0;
}
public static bool WindowSheetOfGlass(IntPtr hWnd)
{
MARGINS Margins = new MARGINS();
Margins.SheetOfGlass();
//Margins set to All:-1 - Sheet Of Glass effect
int result = SafeNativeMethods.DwmExtendFrameIntoClientArea(hWnd, ref Margins);
return result == 0;
}
public static bool WindowDisableRendering(IntPtr hWnd)
{
DWMNCRENDERINGPOLICY NCRP = DWMNCRENDERINGPOLICY.Disabled;
int ncrp = (int)NCRP;
// Disable non-client area rendering on the window.
int result = SafeNativeMethods.DwmSetWindowAttribute(hWnd, DWMWINDOWATTRIBUTE.NCRenderingPolicy, ref ncrp, sizeof(int));
return result == 0;
}
}
}
我将
bottomHeight
设置为3,我发现边框高度包含在表单大小中(表单的大小没有改变)。
所以我给这个表单设置了一个BackgroundImage
,边框就被图像隐藏了。