我遇到了鼠标进入/离开事件的问题。当鼠标按钮被按下并按住控件内的光标然后光标足够快地移出控件时，此事件不会触发。
你能告诉我为什么会这样吗？有没有办法正确获取这些事件？
请检查示例项目以查看它的实际效果：https ://www.dropbox.com/s/w5ra2vzegjtauso/SampleApp.zip
更新。我在这里发现了同样的问题，没有答案。在那里开始赏金。
问问题
13876 次
4 回答
7
编辑：在 Sisyphe 正确指出该行为不适用于具有鼠标交互的元素后，我重写了代码。
该行为可以附加到窗口或任何其他 FrameworkElement。默认情况下，当鼠标左键按下并执行处理程序时，将监视所有包含的元素的 MouseLeave。该行为也可以通过设置仅应用于其关联元素MonitorSubControls="False"。
基本上，该行为的作用（有关更多详细信息，请参阅代码中的注释）：
- 仅在按下鼠标左键时才“活动”
- 监视鼠标位置从元素内部到外部的变化。在这种情况下，执行事件处理程序。
已知的限制（我认为，都可以通过更多的努力来解决，但对我来说似乎不太重要）：
- 不执行转换到包含元素（“内部”边界）的处理程序
- 不保证处理程序的正确执行顺序
- 不能解决缓慢转换到窗口外部的问题，e.LeftButton 被报告为已释放（错误？）。
- 我决定不使用 Win32 钩子，而是使用一个计时器，它不会超过大约每 0.15 秒触发一次（尽管设置的间隔更小，时钟漂移？）。对于快速鼠标移动，评估点可能相距太远，错过刚刚掠过的元素。
此脚本产生以下输出： 将行为附加到窗口，在橙色边框内移动（在释放鼠标按钮的情况下将蓝色边框留在内边界：0），在橙色边框内按下鼠标左键并在窗口外移动（快速）执行离开处理程序 (1 - 4)。释放窗口外的鼠标按钮，移回 goldTextBox (5)，在文本框中按下鼠标左键，离开（快或慢）窗口外再次执行正确的处理程序 (6 - 9)。
Xaml（示例）：
<Window x:Class="WpfApplication1.MouseLeaveControlWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
xmlns:beh="clr-namespace:WpfApplication1.Behavior"
Title="MouseLeaveControlWindow" Height="300" Width="300" x:Name="window" MouseLeave="OnMouseLeave">
<i:Interaction.Behaviors>
<beh:MonitorMouseLeaveBehavior />
</i:Interaction.Behaviors>
<Grid x:Name="grid" MouseLeave="OnMouseLeave" Background="Transparent">
<Grid.RowDefinitions>
<RowDefinition Height="*" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Border x:Name="blueBorder" MouseLeave="OnMouseLeave" Background="SteelBlue" Margin="50" Grid.RowSpan="2" />
<Border x:Name="orangeBorder" MouseLeave="OnMouseLeave" Background="DarkOrange" Margin="70, 70, 70, 20" />
<TextBox x:Name="goldTextBox" MouseLeave="OnMouseLeave" Background="Gold" Margin="70, 20, 70, 70" Grid.Row="1" Text="I'm a TextBox" />
</Grid>
</Window>
后面的代码（仅用于调试目的）：
public partial class MouseLeaveControlWindow : Window
{
public MouseLeaveControlWindow()
{
InitializeComponent();
}
private int i = 0;
private void OnMouseLeave(object sender, MouseEventArgs e)
{
FrameworkElement fe = (FrameworkElement)sender;
if (e.LeftButton == MouseButtonState.Pressed)
{
System.Diagnostics.Debug.WriteLine(string.Format("{0}: Left {1}.", i, fe.Name)); i++;
}
else
{
System.Diagnostics.Debug.WriteLine(string.Format("{0}: Left {1} (Released).", i, fe.Name)); i++;
}
}
}
MonitorMouseLeaveBehavior：
using System;
using System.Linq;
using System.Collections.Generic;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Timers;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Interactivity;
using System.Windows.Interop;
using System.ComponentModel;
using System.Windows.Media;
using WpfApplication1.Helpers;
namespace WpfApplication1.Behavior
{
public class MonitorMouseLeaveBehavior : Behavior<FrameworkElement>
{
[DllImport("user32.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
internal static extern bool GetCursorPos(ref Win32Point pt);
[StructLayout(LayoutKind.Sequential)]
internal struct Win32Point
{
public Int32 X;
public Int32 Y;
};
[DllImport("user32.dll")]
public static extern short GetAsyncKeyState(UInt16 virtualKeyCode);
private enum VK
{
LBUTTON = 0x01
}
private bool _tracking;
private const int _interval = 1;
private Timer _checkPosTimer = new Timer(_interval);
private Dictionary<FrameworkElement, RoutedEventHandlerInfo[]> _leaveHandlersForElement = new Dictionary<FrameworkElement, RoutedEventHandlerInfo[]>();
private Window _window;
private Dictionary<FrameworkElement, Rect> _boundsByElement = new Dictionary<FrameworkElement, Rect>();
private Dictionary<FrameworkElement, bool> _wasInside = new Dictionary<FrameworkElement, bool>();
private List<FrameworkElement> _elements = new List<FrameworkElement>();
/// <summary>
/// If true, all subcontrols are monitored for the mouseleave event when left mousebutton is down.
/// True by default.
/// </summary>
public bool MonitorSubControls { get { return (bool)GetValue(MonitorSubControlsProperty); } set { SetValue(MonitorSubControlsProperty, value); } }
public static readonly DependencyProperty MonitorSubControlsProperty = DependencyProperty.Register("MonitorSubControls", typeof(bool), typeof(MonitorMouseLeaveBehavior), new PropertyMetadata(true, OnMonitorSubControlsChanged));
private static void OnMonitorSubControlsChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
MonitorMouseLeaveBehavior beh = (MonitorMouseLeaveBehavior)d;
beh.AddOrRemoveLogicalChildren((bool)e.NewValue);
}
/// <summary>
/// Initial actions
/// </summary>
protected override void OnAttached()
{
_window = this.AssociatedObject is Window ? (Window)this.AssociatedObject : Window.GetWindow(this.AssociatedObject); // get window
_window.SourceInitialized += (s, e) =>
{
this.AddOrRemoveLogicalChildren(this.MonitorSubControls); // get all monitored elements
this.AttachHandlers(true); // attach mousedown and sizechanged handlers
this.GetAllBounds(); // determine bounds of all elements
_checkPosTimer.Elapsed += (s1, e1) => Dispatcher.BeginInvoke((Action)(() => { CheckPosition(); }));
};
base.OnAttached();
}
protected override void OnDetaching()
{
this.AttachHandlers(false);
base.OnDetaching();
}
/// <summary>
/// Starts or stops monitoring of the AssociatedObject's logical children.
/// </summary>
/// <param name="add"></param>
private void AddOrRemoveLogicalChildren(bool add)
{
if (_window != null && _window.IsInitialized)
{
AddOrRemoveSizeChangedHandlers(false);
_elements.Clear();
if (add)
_elements.AddRange(VisualHelper.FindLogicalChildren<FrameworkElement>(this.AssociatedObject));
_elements.Add(this.AssociatedObject);
AddOrRemoveSizeChangedHandlers(true);
}
}
/// <summary>
/// Attaches/detaches size changed handlers to the monitored elements
/// </summary>
/// <param name="add"></param>
private void AddOrRemoveSizeChangedHandlers(bool add)
{
foreach (var element in _elements)
{
element.SizeChanged -= element_SizeChanged;
if (add) element.SizeChanged += element_SizeChanged;
}
}
/// <summary>
/// Adjusts the stored bounds to the changed size
/// </summary>
void element_SizeChanged(object sender, SizeChangedEventArgs e)
{
FrameworkElement fe = sender as FrameworkElement;
if (fe != null)
GetBounds(fe);
}
/// <summary>
/// Attaches/Detaches MouseLeftButtonDown and SizeChanged handlers
/// </summary>
/// <param name="attach">true: attach, false: detach</param>
private void AttachHandlers(bool attach)
{
AddOrRemoveSizeChangedHandlers(attach);
if (attach)
_window.PreviewMouseLeftButtonDown += window_PreviewMouseLeftButtonDown;
else // detach
_window.PreviewMouseLeftButtonDown -= window_PreviewMouseLeftButtonDown;
}
/// <summary>
/// Gets the bounds for all monitored elements
/// </summary>
private void GetAllBounds()
{
_boundsByElement.Clear();
foreach (var element in _elements)
GetBounds(element);
}
/// <summary>
/// Gets the bounds of the control, which are used to check if the mouse position
/// is located within. Note that this only covers rectangular control shapes.
/// </summary>
private void GetBounds(FrameworkElement element)
{
Point p1 = new Point(0, 0);
Point p2 = new Point(element.ActualWidth, element.ActualHeight);
p1 = element.TransformToVisual(_window).Transform(p1);
p2 = element.TransformToVisual(_window).Transform(p2);
if (element == _window) // window bounds need to account for the border
{
var titleHeight = SystemParameters.WindowCaptionHeight + 2 * SystemParameters.ResizeFrameHorizontalBorderHeight; // not sure about that one
var verticalBorderWidth = SystemParameters.ResizeFrameVerticalBorderWidth;
p1.Offset(-verticalBorderWidth, -titleHeight);
p2.Offset(-verticalBorderWidth, -titleHeight);
}
Rect bounds = new Rect(p1, p2);
if (_boundsByElement.ContainsKey(element))
_boundsByElement[element] = bounds;
else
_boundsByElement.Add(element, bounds);
}
/// <summary>
/// For all monitored elements, detach the MouseLeave event handlers and store them locally,
/// to be executed manually.
/// </summary>
private void RerouteLeaveHandlers()
{
foreach (var element in _elements)
{
if (!_leaveHandlersForElement.ContainsKey(element))
{
var handlers = ReflectionHelper.GetRoutedEventHandlers(element, UIElement.MouseLeaveEvent);
if (handlers != null)
{
_leaveHandlersForElement.Add(element, handlers);
foreach (var handler in handlers)
element.MouseLeave -= (MouseEventHandler)handler.Handler; // detach handlers
}
}
}
}
/// <summary>
/// Reattach all leave handlers that were detached in window_PreviewMouseLeftButtonDown.
/// </summary>
private void ReattachLeaveHandlers()
{
foreach (var kvp in _leaveHandlersForElement)
{
FrameworkElement fe = kvp.Key;
foreach (var handler in kvp.Value)
{
if (handler.Handler is MouseEventHandler)
fe.MouseLeave += (MouseEventHandler)handler.Handler;
}
}
_leaveHandlersForElement.Clear();
}
/// <summary>
/// Checks if the mouse position is inside the bounds of the elements
/// If there is a transition from inside to outside, the leave event handlers are executed
/// </summary>
private void DetermineIsInside()
{
Point p = _window.PointFromScreen(GetMousePosition());
foreach (var element in _elements)
{
if (_boundsByElement.ContainsKey(element))
{
bool isInside = _boundsByElement[element].Contains(p);
bool wasInside = _wasInside.ContainsKey(element) && _wasInside[element];
if (wasInside && !isInside)
ExecuteLeaveHandlers(element);
if (_wasInside.ContainsKey(element))
_wasInside[element] = isInside;
else
_wasInside.Add(element, isInside);
}
}
}
/// <summary>
/// Gets the mouse position relative to the screen
/// </summary>
public static Point GetMousePosition()
{
Win32Point w32Mouse = new Win32Point();
GetCursorPos(ref w32Mouse);
return new Point(w32Mouse.X, w32Mouse.Y);
}
/// <summary>
/// Gets the mouse button state. MouseEventArgs.LeftButton is notoriously unreliable.
/// </summary>
private bool IsMouseLeftButtonPressed()
{
short leftMouseKeyState = GetAsyncKeyState((ushort)VK.LBUTTON);
bool ispressed = leftMouseKeyState < 0;
return ispressed;
}
/// <summary>
/// Executes the leave handlers that were attached to the controls.
/// They have been detached previously by this behavior (see window_PreviewMouseLeftButtonDown), to prevent double execution.
/// After mouseup, they are reattached (see CheckPosition)
/// </summary>
private void ExecuteLeaveHandlers(FrameworkElement fe)
{
MouseDevice mouseDev = InputManager.Current.PrimaryMouseDevice;
MouseEventArgs mouseEvent = new MouseEventArgs(mouseDev, 0) { RoutedEvent = Control.MouseLeaveEvent };
if (_leaveHandlersForElement.ContainsKey(fe))
{
foreach (var handler in _leaveHandlersForElement[fe])
{
if (handler.Handler is MouseEventHandler)
((MouseEventHandler)handler.Handler).Invoke(fe, mouseEvent);
}
}
}
/// <summary>
/// Sets the mouse capture (events outside the window are still directed to it),
/// and tells the behavior to watch out for a missed leave event
/// </summary>
private void window_PreviewMouseLeftButtonDown(object sender, MouseEventArgs e)
{
System.Diagnostics.Debug.WriteLine("--- left mousebutton down ---"); // todo remove
this.RerouteLeaveHandlers();
_tracking = true;
_checkPosTimer.Start();
}
/// <summary>
/// Uses the _tracking field as well as left mouse button state to determine if either
/// leave event handlers should be executed, or monitoring should be stopped.
/// </summary>
private void CheckPosition()
{
if (_tracking)
{
if (IsMouseLeftButtonPressed())
{
this.DetermineIsInside();
}
else
{
_wasInside.Clear();
_tracking = false;
_checkPosTimer.Stop();
System.Diagnostics.Debug.WriteLine("--- left mousebutton up ---"); // todo remove
// invoking ReattachLeaveHandlers() immediately would rethrow MouseLeave for top grid/window
// if both a) mouse is outside window and b) mouse moves. Wait with reattach until mouse is inside window again and moves.
_window.MouseMove += ReattachHandler;
}
}
}
/// <summary>
/// Handles the first _window.MouseMove event after left mouse button was released,
/// and reattaches the MouseLeaveHandlers. Detaches itself to be executed only once.
/// </summary>
private void ReattachHandler(object sender, MouseEventArgs e)
{
ReattachLeaveHandlers();
_window.MouseMove -= ReattachHandler; // only once
}
}
}
VisualHelper.FindLogicalChildren，ReflectionHelper。GetRoutedEventHandlers：
public static List<T> FindLogicalChildren<T>(DependencyObject obj) where T : DependencyObject
{
List<T> children = new List<T>();
foreach (var child in LogicalTreeHelper.GetChildren(obj))
{
if (child != null)
{
if (child is T)
children.Add((T)child);
if (child is DependencyObject)
children.AddRange(FindLogicalChildren<T>((DependencyObject)child)); // recursive
}
}
return children;
}
/// <summary>
/// Gets the list of routed event handlers subscribed to the specified routed event.
/// </summary>
/// <param name="element">The UI element on which the event is defined.</param>
/// <param name="routedEvent">The routed event for which to retrieve the event handlers.</param>
/// <returns>The list of subscribed routed event handlers.</returns>
public static RoutedEventHandlerInfo[] GetRoutedEventHandlers(UIElement element, RoutedEvent routedEvent)
{
var routedEventHandlers = default(RoutedEventHandlerInfo[]);
// Get the EventHandlersStore instance which holds event handlers for the specified element.
// The EventHandlersStore class is declared as internal.
var eventHandlersStoreProperty = typeof(UIElement).GetProperty("EventHandlersStore", BindingFlags.Instance | BindingFlags.NonPublic);
object eventHandlersStore = eventHandlersStoreProperty.GetValue(element, null);
if (eventHandlersStore != null)
{
// Invoke the GetRoutedEventHandlers method on the EventHandlersStore instance
// for getting an array of the subscribed event handlers.
var getRoutedEventHandlers = eventHandlersStore.GetType().GetMethod("GetRoutedEventHandlers", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic);
routedEventHandlers = (RoutedEventHandlerInfo[])getRoutedEventHandlers.Invoke(eventHandlersStore, new object[] { routedEvent });
}
return routedEventHandlers;
}
于 2013-04-15T14:43:38.623 回答
3
方法 #1 - 如果您确定具体细节，它仍然是有效的（作为纯托管解决方案）。
（可以将捕获赋予特定控件以避免问题，但我没有尝试过）
这应该可以帮助您获取事件（“固定”事件）。
关键是在窗口外跟踪鼠标移动（并且仅在鼠标按下时）。
为此，您需要执行此操作capture（但与建议的略有不同，因为这不起作用 - 改为向下/向上）。
private void Window_MouseDown(object sender, MouseEventArgs e)
{
this.CaptureMouse();
}
private void Window_MouseUp(object sender, MouseEventArgs e)
{
this.ReleaseMouseCapture();
}
private void Window_MouseLeave(object sender, MouseEventArgs e)
{
test1.Content = "Mouse left";
}
private void Window_MouseEnter(object sender, MouseEventArgs e)
{
test1.Content = "Mouse entered";
}
private void Window_MouseMove(object sender, MouseEventArgs e)
{
if (Mouse.Captured == this)
{
if (!this.IsMouseInBounds(e))
Window_MouseLeave(sender, e);
else
Window_MouseEnter(sender, e);
}
test2.Content = e.GetPosition(this).ToString();
}
private bool IsMouseInBounds(MouseEventArgs e)
{
var client = ((FrameworkElement)this.Content);
Rect bounds = new Rect(0, 0, client.ActualWidth, client.ActualHeight);
return bounds.Contains(e.GetPosition(this));
}
private Point GetRealPosition(Point mousePoint)
{
return Application.Current.MainWindow.PointFromScreen(mousePoint);
}
注意：
您需要根据您的情况完成此操作。我只是将鼠标“虚拟连接”到那里Enter，Leave并且那里没有任何智能算法（即generated进入/离开将继续触发）。即添加一些标志来实际保存state正确的进入/离开。
此外，我正在测量鼠标是否在窗口的“客户端范围”内。如果您需要在边界等方面进行调整，则需要进行调整。
我也忘了添加明显的 - 连接新事件MouseDown="Window_MouseDown" MouseUp="Window_MouseUp"
于 2013-04-14T15:22:42.720 回答
2
这是“正常”的行为。在 MouseEnter 处理程序中捕获鼠标。
Mouse.Capture(yourUIElement);
然后在 MouseLeave 中释放它，
Mouse.Capture(null);
编辑：更多解释。WPF 不会精确地跟踪鼠标移动。您可以从这样一个事实中推断出，如果您捕获 MouseMove 事件，您可以看到它每隔 20 毫秒报告一次事件，而不是按像素精度......更像是每个事件 8 个像素。
现在这并没有那么可怕，但是如果您碰巧移动了鼠标，WPF 也不会报告窗口外的鼠标移动。这是默认行为。您可以通过 Mouse.Capture 更改它。
现在，您可以想象为什么会出现这个问题。如果您可以将鼠标移到窗口外的速度比鼠标移动报告发生的速度快，那么 WPF 仍然认为它在应用程序内部。
于 2013-04-14T13:05:08.360 回答
2
编辑
如果您需要它 - 我在一个简化的包装器中进行了编辑以便于使用（只需在您的视图模型中添加命令）
方法 #2 - 使用全局鼠标挂钩来跟踪鼠标移动 - 其余的类似于 #1。
实际上，这更多是关于如何从 C# 执行全局挂钩的示例。
在 XAML 中，您可以连接所有 3 个或仅一个、两个事件
my:Hooks.EnterCommand="{Binding EnterCommand}"
my:Hooks.LeaveCommand="{Binding LeaveCommand}"
my:Hooks.MouseMoveCommand="{Binding MoveCommand}"
在您的视图模型中定义命令
RelayCommand _enterCommand;
public RelayCommand EnterCommand
{
get
{
return _enterCommand ?? (_enterCommand = new RelayCommand(param =>
{
var point = (Point)param;
test1.Content = "Mouse entered";
// test2.Content = point.ToString();
},
param => true));
}
}
以及附加的属性（“漂亮”的包装器）......
public static class Hooks
{
private static Dictionary<ContentControl, Action> _hash = new Dictionary<ContentControl, Action>();
#region MouseMoveCommand
public static ICommand GetMouseMoveCommand(ContentControl control) { return (ICommand)control.GetValue(MouseMoveCommandProperty); }
public static void SetMouseMoveCommand(ContentControl control, ICommand value) { control.SetValue(MouseMoveCommandProperty, value); }
public static readonly DependencyProperty MouseMoveCommandProperty =
DependencyProperty.RegisterAttached("MouseMoveCommand", typeof(ICommand), typeof(Hooks), new UIPropertyMetadata(null, OnMouseMoveCommandChanged));
static void OnMouseMoveCommandChanged(DependencyObject depObj, DependencyPropertyChangedEventArgs e)
{
ContentControl control = depObj as ContentControl;
if (control != null && e.NewValue is ICommand)
SetupMouseMove(control);
}
static void Instance_MouseMoveLL(object sender, WinHook.MouseLLMessageArgs e)
{
}
static void OnAutoGeneratingColumn(ICommand command, object sender, DataGridAutoGeneratingColumnEventArgs e)
{
if (command.CanExecute(e)) command.Execute(e);
}
#endregion
#region EnterCommand
public static ICommand GetEnterCommand(ContentControl control) { return (ICommand)control.GetValue(EnterCommandProperty); }
public static void SetEnterCommand(ContentControl control, ICommand value) { control.SetValue(EnterCommandProperty, value); }
public static readonly DependencyProperty EnterCommandProperty =
DependencyProperty.RegisterAttached("EnterCommand", typeof(ICommand), typeof(Hooks), new UIPropertyMetadata(null, OnEnterCommandChanged));
static void OnEnterCommandChanged(DependencyObject depObj, DependencyPropertyChangedEventArgs e)
{
ContentControl control = depObj as ContentControl;
if (control != null && e.NewValue is ICommand)
SetupMouseMove(control);
}
#endregion
#region LeaveCommand
public static ICommand GetLeaveCommand(ContentControl control) { return (ICommand)control.GetValue(LeaveCommandProperty); }
public static void SetLeaveCommand(ContentControl control, ICommand value) { control.SetValue(LeaveCommandProperty, value); }
public static readonly DependencyProperty LeaveCommandProperty =
DependencyProperty.RegisterAttached("LeaveCommand", typeof(ICommand), typeof(Hooks), new UIPropertyMetadata(null, OnLeaveCommandChanged));
static void OnLeaveCommandChanged(DependencyObject depObj, DependencyPropertyChangedEventArgs e)
{
ContentControl control = depObj as ContentControl;
if (control != null && e.NewValue is ICommand)
SetupMouseMove(control);
}
#endregion
static void SetupMouseMove(ContentControl control)
{
Action onmove;
if (_hash.TryGetValue(control, out onmove) == false)
{
onmove = () =>
{
var entered = false;
var moveCommand = control.GetValue(Hooks.MouseMoveCommandProperty) as ICommand;
var enterCommand = control.GetValue(Hooks.EnterCommandProperty) as ICommand;
var leaveCommand = control.GetValue(Hooks.LeaveCommandProperty) as ICommand;
// hook is invoked on the 'caller thread' (i.e. your GUI one) so it's safe
// don't forget to unhook and dispose / release it, handle unsubscribe for events
WinHook.Instance.MouseMoveLL += (s, e) =>
{
Point point = control.PointFromScreen(new Point(e.Message.Pt.X, e.Message.Pt.Y));
if (moveCommand != null && moveCommand.CanExecute(point))
moveCommand.Execute(point);
var newEntered = control.IsMouseInBounds(point); // don't use 'IsMouseOver'
if (newEntered != entered)
{
entered = newEntered;
if (entered)
{
if (enterCommand != null && enterCommand.CanExecute(point))
enterCommand.Execute(point);
}
else
{
if (leaveCommand != null && leaveCommand.CanExecute(point))
leaveCommand.Execute(point);
}
}
};
};
control.Loaded += (s, e) => onmove();
_hash[control] = onmove;
}
}
private static bool IsMouseInBounds(this ContentControl control, Point point)
{
var client = ((FrameworkElement)control.Content);
Rect bounds = new Rect(0, 0, client.ActualWidth, client.ActualHeight);
return bounds.Contains(point);
}
}
您可以使用文章中的HookManager。
或最小的钩子代码（请注意，需要正确的 IDisoposable、异常处理等）：
public sealed class WinHook : IDisposable
{
public static readonly WinHook Instance = new WinHook();
public const int WH_MOUSE_LL = 14;
public const uint WM_MOUSEMOVE = 0x0200;
public delegate void MouseLLMessageHandler(object sender, MouseLLMessageArgs e);
public delegate int HookProc(int nCode, IntPtr wParam, IntPtr lParam);
[DllImport("kernel32.dll", ExactSpelling = true, CharSet = CharSet.Auto)]
public static extern int GetCurrentThreadId();
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, SetLastError = true)]
public static extern int SetWindowsHookEx(int idHook, HookProc lpfn, IntPtr hInstance, int threadId);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, SetLastError = true)]
public static extern bool UnhookWindowsHookEx(int idHook);
[DllImport("user32.dll", CharSet = CharSet.Auto, CallingConvention = CallingConvention.StdCall, SetLastError = true)]
public static extern int CallNextHookEx(int idHook, int nCode, IntPtr wParam, IntPtr lParam);
[DllImport("kernel32.dll", CharSet = CharSet.Auto)]
public static extern IntPtr GetModuleHandle(string lpModuleName);
[StructLayout(LayoutKind.Sequential)]
public struct POINT
{
public int X;
public int Y;
}
[StructLayout(LayoutKind.Sequential)]
public class MouseLLHookStruct
{
public POINT Pt;
public uint mouseData;
public uint flags;
public uint time;
public uint dwExtraInfo;
}
public class MouseLLMessageArgs : EventArgs
{
public bool IsProcessed { get; set; }
public MouseLLHookStruct Message { get; private set; }
public MouseLLMessageArgs(MouseLLHookStruct message) { this.Message = message; }
}
static IntPtr GetModuleHandle()
{
using (Process process = Process.GetCurrentProcess())
using (ProcessModule module = process.MainModule)
return GetModuleHandle(module.ModuleName);
}
public event MouseLLMessageHandler MouseMoveLL;
int _hLLMouseHook = 0;
HookProc LLMouseHook;
private WinHook()
{
IntPtr hModule = GetModuleHandle();
LLMouseHook = LowLevelMouseProc;
_hLLMouseHook = SetWindowsHookEx(WH_MOUSE_LL, LLMouseHook, hModule, 0);
if (_hLLMouseHook == 0) { } // "failed w/ an error code: {0}", new Win32Exception(Marshal.GetLastWin32Error()).Message
}
public void Release()
{
if (_hLLMouseHook == 0) return;
int hhook = _hLLMouseHook;
_hLLMouseHook = 0;
bool ret = UnhookWindowsHookEx(hhook);
if (ret == false) { } // "failed w/ an error code: {0}", new Win32Exception(Marshal.GetLastWin32Error()).Message
}
public int LowLevelMouseProc(int nCode, IntPtr wParam, IntPtr lParam)
{
if (nCode >= 0 && lParam.ToInt32() > 0
&& wParam.ToInt32() == (int)WM_MOUSEMOVE)
{
MouseLLHookStruct msg = (MouseLLHookStruct)Marshal.PtrToStructure(lParam, typeof(MouseLLHookStruct));
MouseLLMessageArgs args = new MouseLLMessageArgs(msg);
if (MouseMoveLL != null)
MouseMoveLL(this, args);
if (args.IsProcessed)
return -1; // return 1;
}
return CallNextHookEx(_hLLMouseHook, nCode, wParam, lParam);
}
// implement IDisposable properly and call `Release` for unmanaged resources / hook
public void Dispose() { }
}
注意：全局鼠标挂钩因性能问题而臭名昭著。而且你不能使用本地的（推荐但大多数时候没用） - 因为它不会让鼠标移动。
还要避免在事件中放置任何“重”的东西 - 或从中“产生”的任何东西。实际上，您可以花在处理事件上的时间是有限制的——否则您的钩子将被移除，即停止工作。如果你需要从事件中做一些处理，弹出一个新线程并调用回来。
我最喜欢的解决方案实际上是给钩子自己的线程，然后需要调用事件——但这超出了范围并且有点复杂（你需要一个“泵”等）。
至于“为什么”这一切都是必要的：
我不喜欢猜测，但似乎事件受到了限制——当“越界”时，关键的“一个”被错过了，类似的事情。无论如何，无论您怎么看，这都是关于鼠标移动的。
于 2013-04-15T19:12:37.100 回答