Hit Result Behavior : Mouse « Windows Presentation Foundation « C# / C Sharp

1. C# / C Sharp
2. Windows Presentation Foundation
3. Mouse

Hit Result Behavior

  
<Window x:Class="WpfApplication1.HitTestExample"
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  Title="WpfApplication1" Height="300" Width="300">


  <Canvas x:Name="canvas1"
    MouseLeftButtonDown="OnMouseLeftButtonDown">
    <Rectangle Canvas.Left="20" Canvas.Top="20" Width="100"
      Height="60" Stroke="Black" Fill="LightBlue" Opacity="0.7" />

    <Rectangle Canvas.Left="70" Canvas.Top="50" Width="100"
      Height="60" Stroke="Black" Fill="LightBlue" Opacity="0.7" />


    <Rectangle Canvas.Left="150" Canvas.Top="80" Width="100"
      Height="60" Stroke="Black" Fill="LightBlue" Opacity="0.7" />


    <Rectangle Canvas.Left="20" Canvas.Top="100" Width="50"
      Height="50" Stroke="Black" Fill="LightBlue" Opacity="0.7" />


    <Rectangle Canvas.Left="40" Canvas.Top="60" Width="50"
      Height="50" Stroke="Black" Fill="LightBlue" Opacity="0.7" />


    <Rectangle Canvas.Left="30" Canvas.Top="130" Width="50"
      Height="50" Stroke="Black" Fill="LightBlue" Opacity="0.7" />


  </Canvas>
</Window>

//File:Window.xaml.cs
using System;
using System.Collections.Generic;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Shapes;


namespace WpfApplication1
{
    public partial class HitTestExample : Window
    {
        private List<Rectangle> hitList = new List<Rectangle>();
        private EllipseGeometry hitArea = new EllipseGeometry();
        public HitTestExample()
        {
            InitializeComponent();
        }
        private void OnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            foreach (Rectangle rect in canvas1.Children)
            {
                rect.Fill = Brushes.Red;
            }

            Point pt = e.GetPosition(canvas1);
            hitArea = new EllipseGeometry(pt, 1.0, 1.0);
            hitList.Clear();
            VisualTreeHelper.HitTest(canvas1, null,new HitTestResultCallback(HitTestCallback),new GeometryHitTestParameters(hitArea));
            if (hitList.Count > 0)
            {
                foreach (Rectangle rect in hitList)
                {
                    rect.Fill = Brushes.Blue;
                }
                Console.WriteLine("You hit " + hitList.Count.ToString() + " rectangles.");
            }
        }
        public HitTestResultBehavior HitTestCallback(HitTestResult result)
        {
            IntersectionDetail intersectionDetail = ((GeometryHitTestResult)result).IntersectionDetail;
            switch (intersectionDetail)
            {
                case IntersectionDetail.FullyContains:
                    hitList.Add((Rectangle)result.VisualHit);
                    return HitTestResultBehavior.Continue;
                case IntersectionDetail.Intersects:
                    return HitTestResultBehavior.Continue;
                case IntersectionDetail.FullyInside:
                    return HitTestResultBehavior.Continue;
                default:
                    return HitTestResultBehavior.Stop;
            }
        }
    }
}

   
    
  

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6.	Handler MouseLeftButtonDown and MouseLeftButtonUp events
7.	Mouse Enter and leave a Border
8.	Make an object follow the mouse pointer as it moves on the screen.
9.	Use Mouse.AddPreviewMouseDownHandler(myEllipse, PreviewMouseDownEllipse);
10.	Use Mouse.AddMouseDownHandler(myEllipse, MouseDownEllipse);
11.	Use Mouse.PreviewMouseDown /Mouse.MouseDown Attribute from Grid element
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13.	Grid MouseLeftButtonDown
14.	Grid MouseLeftButtonUp
15.	UI Element Mouse Clicked Events
16.	Handles the MouseDown event on the Canvas
17.	Handles the MouseDown event on the UniformGrid
18.	Mouse cursor override and clear
19.	Check the mouse event source
20.	Use the Mouse Wheel action methods that are defined by the IScrollInfo interface
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22.	Use Mouse.Capture to let a Control capture an event
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