WPF bind baidu Image

 as there baidu image has protect refer from other site to use.

 need download i use request header add referer:http://www.baidu.com

<Window x:Class="WpfApplication1.WindMsg"

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

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

        Title="WindMsg" Height="300" Width="300" Closing="Window_Closing" Loaded="Window_Loaded">

    <Grid>

        <Image Name="img" Stretch="Uniform" Source="{Binding BitmapImg}"/>

        <Button Content="{Binding Text}" Height="65" HorizontalAlignment="Left" Margin="58,48,0,0" Name="button1" VerticalAlignment="Top" Width="160" Click="button1_Click" />

    </Grid>

</Window>

 public WindMsg()

        {

            InitializeComponent();

            d = new ImageData() { Url = "http://img0.imgtn.bdimg.com/it/u=3028557787,2951839071&fm=15&gp=0.jpg", Text = "test button text" };

            this.DataContext = d;

        }

        ImageData d;

        public class ImageData

        {

            public string Url { get; set; }

            public string Text { get; set; }

            public ImageSource BitmapImg

            {

                get { return GetImageData(); }

                set { }

            }

            BitmapImage GetImageData()

            {

                using (WebClient wc = new WebClient())

                {

                    wc.Headers.Add("Referer", "http://www.baidu.com");

                    Stream stream = wc.OpenRead(Url);

                    BitmapImage b = new BitmapImage();

                    b.BeginInit();

                    b.StreamSource = stream;

                    b.EndInit();

                    return b;

                }

            }

        }

 缓冲图片，延迟加载

// Create source

BitmapImage myBitmapImage = new BitmapImage();

// BitmapImage.UriSource must be in a BeginInit/EndInit block

myBitmapImage.BeginInit();

myBitmapImage.UriSource = new Uri(str, UriKind.Absolute);

// To save significant application memory, set the DecodePixelWidth or  

// DecodePixelHeight of the BitmapImage value of the image source to the desired 

// height or width of the rendered image. If you don't do this, the application will 

// cache the image as though it were rendered as its normal size rather then just 

// the size that is displayed.

// Note: In order to preserve aspect ratio, set DecodePixelWidth

// or DecodePixelHeight but not both.

myBitmapImage.DecodePixelWidth = 2048;

myBitmapImage.EndInit();

//set image source