WndProc
并在消息到达时开始处理它们。请问有人能展示一个在WPF中实现同样功能的例子吗?System.Windows.Interop
命名空间来实现此操作,其中包含一个名为 HwndSource
的类。using System;
using System.Windows;
using System.Windows.Interop;
namespace WpfApplication1
{
public partial class Window1 : Window
{
public Window1()
{
InitializeComponent();
}
protected override void OnSourceInitialized(EventArgs e)
{
base.OnSourceInitialized(e);
HwndSource source = PresentationSource.FromVisual(this) as HwndSource;
source.AddHook(WndProc);
}
private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
// Handle messages...
return IntPtr.Zero;
}
}
}
完全取自卓越的博客文章:使用自定义WndProc在WPF应用程序中 by Steve Rands
实际上,据我所知,使用 HwndSource
和 HwndSourceHook
在 WPF 中确实可以做到这一点。 请参阅MSDN 上的此帖子作为示例(以下包括相关代码)。
// 'this' is a Window
HwndSource source = HwndSource.FromHwnd(new WindowInteropHelper(this).Handle);
source.AddHook(new HwndSourceHook(WndProc));
private static IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
// do stuff
return IntPtr.Zero;
}
现在,我不太确定为什么你想在WPF应用程序中处理Windows消息(除非它是与另一个WinForms应用程序交互的最明显形式)。WPF的设计思想和API的性质与WinForms非常不同,因此我建议你只需更加熟悉WPF,以了解为什么没有WndProc的等效物。
WM_MOUSEWHEEL
消息的唯一方法是将WndProc
添加到WPF窗口中。这对我很有效,而官方的MouseWheelEventHandler
并没有像预期的那样工作。我无法正确地将WPF时空子弹对齐以获得可靠的MouseWheelEventHandler
行为,因此需要直接访问WndProc
。 - Chris OHwndSource src = HwndSource.FromHwnd(new WindowInteropHelper(this).Handle);
src.AddHook(new HwndSourceHook(WndProc));
.......
public IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
{
if(msg == THEMESSAGEIMLOOKINGFOR)
{
//Do something here
}
return IntPtr.Zero;
}
如果您不介意参考WinForms,您可以使用更加面向MVVM的解决方案,它不会将服务与视图耦合在一起。您需要创建和初始化一个System.Windows.Forms.NativeWindow,它是一个轻量级窗口,可以接收消息。
public abstract class WinApiServiceBase : IDisposable
{
/// <summary>
/// Sponge window absorbs messages and lets other services use them
/// </summary>
private sealed class SpongeWindow : NativeWindow
{
public event EventHandler<Message> WndProced;
public SpongeWindow()
{
CreateHandle(new CreateParams());
}
protected override void WndProc(ref Message m)
{
WndProced?.Invoke(this, m);
base.WndProc(ref m);
}
}
private static readonly SpongeWindow Sponge;
protected static readonly IntPtr SpongeHandle;
static WinApiServiceBase()
{
Sponge = new SpongeWindow();
SpongeHandle = Sponge.Handle;
}
protected WinApiServiceBase()
{
Sponge.WndProced += LocalWndProced;
}
private void LocalWndProced(object sender, Message message)
{
WndProc(message);
}
/// <summary>
/// Override to process windows messages
/// </summary>
protected virtual void WndProc(Message message)
{ }
public virtual void Dispose()
{
Sponge.WndProced -= LocalWndProced;
}
}
public class WindowsMessageListenerService : WinApiServiceBase
{
protected override void WndProc(Message message)
{
Debug.WriteLine(message.msg);
}
}
using System;
using System.Windows.Interactivity;
using System.Windows; // For Window in behavior
using System.Windows.Interop; // For Hwnd
public class WindowResizeEvents : Behavior<Window>
{
public event EventHandler Resized;
public event EventHandler Resizing;
public event EventHandler Maximized;
public event EventHandler Minimized;
public event EventHandler Restored;
public static DependencyProperty IsAppAskCloseProperty = DependencyProperty.RegisterAttached("IsAppAskClose", typeof(bool), typeof(WindowResizeEvents));
public Boolean IsAppAskClose
{
get { return (Boolean)this.GetValue(IsAppAskCloseProperty); }
set { this.SetValue(IsAppAskCloseProperty, value); }
}
// called when the behavior is attached
// hook the wndproc
protected override void OnAttached()
{
base.OnAttached();
AssociatedObject.Loaded += (s, e) =>
{
WireUpWndProc();
};
}
// call when the behavior is detached
// clean up our winproc hook
protected override void OnDetaching()
{
RemoveWndProc();
base.OnDetaching();
}
private HwndSourceHook _hook;
private void WireUpWndProc()
{
HwndSource source = HwndSource.FromVisual(AssociatedObject) as HwndSource;
if (source != null)
{
_hook = new HwndSourceHook(WndProc);
source.AddHook(_hook);
}
}
private void RemoveWndProc()
{
HwndSource source = HwndSource.FromVisual(AssociatedObject) as HwndSource;
if (source != null)
{
source.RemoveHook(_hook);
}
}
private const Int32 WM_EXITSIZEMOVE = 0x0232;
private const Int32 WM_SIZING = 0x0214;
private const Int32 WM_SIZE = 0x0005;
private const Int32 SIZE_RESTORED = 0x0000;
private const Int32 SIZE_MINIMIZED = 0x0001;
private const Int32 SIZE_MAXIMIZED = 0x0002;
private const Int32 SIZE_MAXSHOW = 0x0003;
private const Int32 SIZE_MAXHIDE = 0x0004;
private const Int32 WM_QUERYENDSESSION = 0x0011;
private const Int32 ENDSESSION_CLOSEAPP = 0x1;
private const Int32 WM_ENDSESSION = 0x0016;
private IntPtr WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, ref Boolean handled)
{
IntPtr result = IntPtr.Zero;
switch (msg)
{
case WM_SIZING: // sizing gets interactive resize
OnResizing();
break;
case WM_SIZE: // size gets minimize/maximize as well as final size
{
int param = wParam.ToInt32();
switch (param)
{
case SIZE_RESTORED:
OnRestored();
break;
case SIZE_MINIMIZED:
OnMinimized();
break;
case SIZE_MAXIMIZED:
OnMaximized();
break;
case SIZE_MAXSHOW:
break;
case SIZE_MAXHIDE:
break;
}
}
break;
case WM_EXITSIZEMOVE:
OnResized();
break;
// Windows is requesting app to close.
// See http://msdn.microsoft.com/en-us/library/windows/desktop/aa376890%28v=vs.85%29.aspx.
// Use the default response (yes).
case WM_QUERYENDSESSION:
IsAppAskClose = true;
break;
}
return result;
}
private void OnResizing()
{
if (Resizing != null)
Resizing(AssociatedObject, EventArgs.Empty);
}
private void OnResized()
{
if (Resized != null)
Resized(AssociatedObject, EventArgs.Empty);
}
private void OnRestored()
{
if (Restored != null)
Restored(AssociatedObject, EventArgs.Empty);
}
private void OnMinimized()
{
if (Minimized != null)
Minimized(AssociatedObject, EventArgs.Empty);
}
private void OnMaximized()
{
if (Maximized != null)
Maximized(AssociatedObject, EventArgs.Empty);
}
}
<Window x:Class="MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml
xmlns:i="clr-namespace:System.Windows.Interactivity;assembly=System.Windows.Interactivity"
xmlns:behaviors="clr-namespace:RapidCoreConfigurator._Behaviors"
Title="name" Height="500" Width="750" BorderBrush="Transparent">
<i:Interaction.Behaviors>
<behaviors:WindowResizeEvents IsAppAskClose="{Binding IsRequestClose, Mode=OneWayToSource}"
Resized="Window_Resized"
Resizing="Window_Resizing" />
</i:Interaction.Behaviors>
...
</Window>
using Microsoft.Win32;
SystemEvents.PowerModeChanged += SystemEvents_PowerModeChanged;
SystemEvents.SessionSwitch += SystemEvents_SessionSwitch;
SystemEvents.SessionEnding += SystemEvents_SessionEnding;
SystemEvents.SessionEnded += SystemEvents_SessionEnded;
private async void SystemEvents_PowerModeChanged(object sender, PowerModeChangedEventArgs e)
{
await vm.PowerModeChanged(e.Mode);
}
private async void SystemEvents_PowerModeChanged(object sender, PowerModeChangedEventArgs e)
{
await vm.PowerModeChanged(e.Mode);
}
private async void SystemEvents_SessionSwitch(object sender, SessionSwitchEventArgs e)
{
await vm.SessionSwitch(e.Reason);
}
private async void SystemEvents_SessionEnding(object sender, SessionEndingEventArgs e)
{
if (e.Reason == SessionEndReasons.Logoff)
{
await vm.UserLogoff();
}
}
private async void SystemEvents_SessionEnded(object sender, SessionEndedEventArgs e)
{
if (e.Reason == SessionEndReasons.Logoff)
{
await vm.UserLogoff();
}
}
有多种方法可以使用WPF中的WndProc处理消息(例如,使用HwndSource等),但通常这些技术是保留用于与无法直接通过WPF处理的消息进行交互。大多数WPF控件甚至不是Win32中窗口的窗口(并且通过延伸Windows.Forms),因此它们不会有WndProcs。
WndProc
可覆盖,但是System.Windows.Interop
允许您通过HwndSource.FromHwnd
或PresentationSource.FromVisual(someForm) as HwndSource
获取HwndSource
对象,您可以将一个特殊模式的委托绑定到该对象。这个委托有许多与WndProc
消息对象相同的参数。 - Andrew GrayWPF不支持WinForms类型的wndprocs
您可以在适当的WPF元素中托管HWndHost,然后覆盖Hwndhost的wndproc,但据我所知,这是最接近的方法。
http://msdn.microsoft.com/en-us/library/ms742522.aspx
http://blogs.msdn.com/nickkramer/archive/2006/03/18/554235.aspx
简短的回答是你不能。WndProc 通过向 Win32 级别的 HWND 传递消息来工作。WPF 窗口没有 HWND,因此无法参与 WndProc 消息。基本的 WPF 消息循环确实位于 WndProc 之上,但它将它们从核心 WPF 逻辑中抽象出来。
您可以使用 HWndHost 并获取其 WndProc。然而,这几乎肯定不是您想要做的。对于大多数目的,WPF 不依赖于 HWND 和 WndProc。您的解决方案几乎肯定依赖于在 WPF 中进行更改,而不是在 WndProc 中进行更改。