几个mouse事件的特点

Posted 2023-04-27

参考技术A 1.mouseover() : 如果鼠标指针穿过任何子元素，同样会触发 mouseover 事件。

注：比如div使用了mouseover 事件,鼠标在进入div到span再出去,会触发3次mouseover 事件;

2.mouseenter() : 只有在鼠标指针穿过被选元素时，才会触发 mouseenter 事件。

注：比如div使用了mouseenter 事件,鼠标在进入div到span再出去,会触发1次mouseenter事件;

3.mouseout() : 如果鼠标指针离开任何子元素，同样会触发 mouseout 事件。

注：比如div使用了mouseout 事件,鼠标在进入div到span再出去,会触发3次mouseout 事件;

4.mouseleave() : 只有在鼠标指针离开被选元素时，才会触发 mouseleave 事件。

注：比如div使用了mouseleave 事件,鼠标在进入div到span再出去,会触发1次mouseleave 事件;

所以它们的区别就是mouseover和mouseout拥有冒泡属性，将 mouseout() 换成 mouseleave() 即可！

判断Mouse事件源类型

  //鼠标事件源类型

    public enum MouseEventSource
    {
        Mouse,
        Pen,
        Touch
    }
    /// <summary>
    /// MainWindow.xaml 的交互逻辑
    /// </summary>
    public partial class MainWindow : Window
    {
        public MainWindow()
        {
            InitializeComponent();
            inkcv.PreviewMouseDown += Inkcv_PreviewMouseDown;
            inkcv.PreviewMouseMove += Inkcv_PreviewMouseMove;
            inkcv.PreviewMouseUp += Inkcv_PreviewMouseUp;
            
        }

        private void Inkcv_PreviewMouseUp(object sender, MouseButtonEventArgs e)
        {
            var s = GetMouseEventSource();
            result.Text = "mouse up,Source: "+ s.ToString();
        }

        private void Inkcv_PreviewMouseMove(object sender, MouseEventArgs e)
        {
            if (e.LeftButton==MouseButtonState.Pressed)
            {
                result.Text ="mouse move,Source: "+ GetMouseEventSource().ToString();
            }          

        }

        private void Inkcv_PreviewMouseDown(object sender, MouseButtonEventArgs e)
        {
            var s = GetMouseEventSource();
            result.Text = "mouse previewdown,Source: "+ s.ToString();
       }

        [DllImport("user32.dll")]
        private static extern uint GetMessageExtraInfo();
        public static MouseEventSource GetMouseEventSource()
        {
            uint extra = GetMessageExtraInfo();
            bool isTouchOrPen = ((extra & 0xffffff00) == 0xff515700);
            if (!isTouchOrPen)
                return MouseEventSource.Mouse;
            bool isTouch = ((extra & 0x00000080) == 0x00000080);
            return isTouch ? MouseEventSource.Touch : MouseEventSource.Pen;
        }
    }