Silverlight实用窍门序列：3.Silverlight鼠标动态绘制矩形【实例源码下载】

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

namespace SLRectangle
{
    public partial class MainPage : UserControl
    {
        public MainPage()
        {
            InitializeComponent();
        }
        private Rectangle rect; //声明一个矩形引用
        private Point origPoint; //设置一个鼠标点的引用
        private bool isAddMouseEvent = false; //标示是否添加了鼠标事件

        /// <summary>
        /// 鼠标左键按下去的时候产生相应的矩形框控件，添加相应的移动控件事件和鼠标左键弹起事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Handle_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
        {
            rect = new Rectangle();
            origPoint = e.GetPosition(AddUC);

            rect.SetValue(Canvas.LeftProperty, origPoint.X); //设置矩形的起始X坐标
            rect.SetValue(Canvas.TopProperty, origPoint.Y);  //设置矩形的起始Y坐标
            rect.Opacity = 1;          //设置本控件透明度
            rect.Fill = new SolidColorBrush(Colors.Blue);
            rect.RadiusX = 10;//为了让矩形美观一些设置了圆角属性
            rect.RadiusY = 10;
            AddUC.MouseMove += Handle_MouseMove; //为Canvas面板加载MouseMove事件
            AddUC.MouseLeftButtonUp += Handle_MouseLeftButtonUp;//为Canvas面板加载MouseLeftButtonUp事件
            AddUC.Children.Add(rect); //在Canvas面板中添加矩形
        }

        /// <summary>
        /// 当鼠标左键绘制完成，弹起鼠标的时候移除本页面的鼠标事件绑定。
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Handle_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        {
            AddUC.MouseLeftButtonUp -= Handle_MouseLeftButtonUp;
            AddUC.MouseMove -= Handle_MouseMove;
        }
        /// <summary>
        /// 当鼠标按下去移动的时候，矩形框控件也相应的改变大小以形成相应的框
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void Handle_MouseMove(object sender, MouseEventArgs e)
        {
            Point curPoint = e.GetPosition(AddUC);
            if (curPoint.X > origPoint.X) 
            {
                rect.Width = curPoint.X - origPoint.X;
            }
            if (curPoint.X < origPoint.X)
            {
                rect.SetValue(Canvas.LeftProperty, curPoint.X);
                rect.Width = origPoint.X - curPoint.X;
            }
            if (curPoint.Y > origPoint.Y)
            {
                rect.Height = curPoint.Y - origPoint.Y;
            }
            if (curPoint.Y < origPoint.Y)
            {
                rect.SetValue(Canvas.TopProperty, curPoint.Y);
                rect.Height = origPoint.Y - curPoint.Y;
            }

        }

        private void button1_Click(object sender, RoutedEventArgs e)
        {
            //监测是否已经为鼠标绘制状态。如果不是那么则绑定为鼠标绘制状态，且设置此按钮为不可用状态
            if (isAddMouseEvent == false)
            {
                this.AddUC.MouseLeftButtonDown += Handle_MouseLeftButtonDown;
                isAddMouseEvent = true;
                this.button1.IsEnabled = false;

            }
        }

    }
}

<UserControl x:Class="SLRectangle.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    d:DesignHeight="1000" d:DesignWidth="1000" xmlns:sdk="http://schemas.microsoft.com/winfx/2006/xaml/presentation/sdk">

    <Grid x:Name="LayoutRoot"  >
        <Canvas x:Name="AddUC"   HorizontalAlignment="Stretch"  Background="Black"   VerticalAlignment="Stretch" Width="1920" Height="1080">
        </Canvas>
        <Button Width="97" Height="30" Content="点我开始绘制矩形" x:Name="button1" Margin="15,10,0,0"   VerticalAlignment="Top" HorizontalAlignment="Left" Click="button1_Click"></Button>
       
    </Grid>
</UserControl>