动态向Canvas添加布局对象和元素

动态向Canvas添加布局对象和元素

前台代码：

<UserControl x:Class="SilverlightApplication45.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="640" d:DesignWidth="400">

    <Grid x:Name="LayoutRoot">
        <Canvas x:Name="parentCanvas" Background="SlateGray">
            <TextBox x:Name="tbLeft" FontSize="18" Width="80" Height="30" Text="0"
                       Canvas.Left="530" Canvas.Top="60"/>

            <TextBox x:Name="tbTop" FontSize="18" Width="80" Height="30" Text="0"
                       Canvas.Left="530" Canvas.Top="140"/>
            
            <TextBlock Text="Canvas.Left:" FontSize="18" Canvas.Left="500" Canvas.Top="20"/>
            <TextBlock Text="Canvas.Top:" FontSize="18" Canvas.Left="500" Canvas.Top="100"/>
            
            <Button x:Name="btnAdd" Content="添加" Width="100" Height="40" FontSize="18"
                    Canvas.Left="520" Canvas.Top="200" Click="btnAdd_Click"/>

            <Button x:Name="btnClear" Content="清除" Width="100" Height="40" FontSize="18"
                    Canvas.Left="520" Canvas.Top="280" Click="btnClear_Click"/>
        </Canvas>
    </Grid>
</UserControl>

 

后台代码：

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 SilverlightApplication45
{
    public partial class MainPage : UserControl
    {
        private Canvas myCanvas = new Canvas();
        public MainPage()
        {
            InitializeComponent();
            myCanvas.Width = 480;
            myCanvas.Height = 400;
            myCanvas.Background = new SolidColorBrush(Colors.Red);
            this.parentCanvas.Children.Add(myCanvas);
        }

        private void btnAdd_Click(object sender, RoutedEventArgs e)
        {
            Ellipse myell = new Ellipse();
            myell.Width = 40;
            myell.Height = 40;
            myell.StrokeThickness = 3;
            myell.Stroke = new SolidColorBrush(Colors.Black);
            myell.Fill = new SolidColorBrush(Colors.Green);
            Canvas.SetLeft(myell, Convert.ToDouble(this.tbLeft.Text));
            Canvas.SetTop(myell, Convert.ToDouble(this.tbTop.Text));
            myCanvas.Children.Add(myell);
        }

        private void btnClear_Click(object sender, RoutedEventArgs e)
        {
            myCanvas.Children.Clear();
        }
    }
}