C# wpf InkCanvas 保存图片jpg

前端xaml页面代码

<Window x:Class="WpfApplication6.MainWindow"

        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

        Title="MainWindow" Height="" Width="">

    <Grid>

        <Canvas x:Name="Screen" Width="96  " Height="">

            <InkCanvas x:Name="inkCanvas" Height="" Width="" Canvas.Left="-203" Canvas.Top="-108" />

            <TextBlock Canvas.Left="" Canvas.Top="" x:Name="VSSize" ></TextBlock>

        </Canvas>

        <Button Content="保存" Height="" HorizontalAlignment="Right" Margin="0,274,0,12" Name="button1" Width="" Click="button1_Click" />

    </Grid>

</Window>

后台cs页面代码

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Windows;

using System.Windows.Controls;

using System.Windows.Data;

using System.Windows.Documents;

using System.Windows.Input;

using System.Windows.Media;

using System.Windows.Media.Imaging;

using System.Windows.Navigation;

using System.Windows.Shapes;

using System.IO;

using System.Windows.Ink;

namespace WpfApplication6

{

    /// <summary>

    /// MainWindow.xaml 的交互逻辑

    /// </summary>

    public partial class MainWindow : Window

    {

        DrawingAttributes drawingAttributes;

        public MainWindow()

        {

            InitializeComponent();

            //创建 DrawingAttributes 类的一个实例

            drawingAttributes = new DrawingAttributes();

            //将 InkCanvas 的 DefaultDrawingAttributes 属性的值赋成创建的 DrawingAttributes 类的对象的引用

            //InkCanvas 通过 DefaultDrawingAttributes 属性来获取墨迹的各种设置，该属性的类型为 DrawingAttributes 型

            inkCanvas.DefaultDrawingAttributes = drawingAttributes;

            //设置 DrawingAttributes 的 Color 属性设置颜色

            drawingAttributes.Color = Colors.Red;

        }

        private void button1_Click(object sender, RoutedEventArgs e)

        {

            RenderTargetBitmap rtb = new RenderTargetBitmap(, , this.Screen.Width, this.Screen.Height, PixelFormats.Default);

            rtb.Render(this.inkCanvas);

            BmpBitmapEncoder encoder = new BmpBitmapEncoder();

            encoder.Frames.Add(BitmapFrame.Create(rtb));

            string file = "d:\\xxx.jpg";

            using (Stream stm = File.Create(file))

            {

                encoder.Save(stm);

            }

        }

    }

}