分享一个网络图片控件(WebImage for wp8)

  闲话不多说，直接上代码！！！转载请附上原作者地址哦！！！thx！！！

  WebImage.xaml页面代码如下：

 

<UserControl x:Class="WpDemo.Controls.WebImage"      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"    FontFamily="{StaticResource PhoneFontFamilyNormal}"    FontSize="{StaticResource PhoneFontSizeNormal}"    Foreground="{StaticResource PhoneForegroundBrush}"    d:DesignHeight="480" d:DesignWidth="480">    <Grid x:Name="LayoutRoot">        <Image x:Name="ImgShow" Stretch="UniformToFill" Visibility="Collapsed"/>        <Grid x:Name="gdWait">            <Rectangle x:Name="rectProgress" Fill="#FFFFB3E0" Stroke="Black" VerticalAlignment="Bottom"/>            <TextBlock x:Name="tbProgress" HorizontalAlignment="Center" TextWrapping="Wrap" VerticalAlignment="Center" Foreground="White" Text="0"/>        </Grid>    </Grid></UserControl>

WebImage.xaml.cs类如下:

using System;using System.Collections.Generic;using System.Linq;using System.Net;using System.Windows;using System.Windows.Controls;using System.Windows.Navigation;using Microsoft.Phone.Controls;using Microsoft.Phone.Shell;using System.Windows.Media;using System.Windows.Media.Imaging;using System.ComponentModel;using System.IO;namespace WpDemo.Controls{    public partial class WebImage : UserControl    {        private static String CacheFolder = "cloud_cache_image";        private BitmapImage _imgSource = null;        public static readonly DependencyProperty SourceProperty = DependencyProperty.Register("Source", typeof(ImageSource), typeof(WebImage), null);        public static readonly DependencyProperty StretchProperty = DependencyProperty.Register("Stretch", typeof(Stretch), typeof(WebImage), new PropertyMetadata(Stretch.UniformToFill));        public static readonly DependencyProperty ImgUriProperty = DependencyProperty.Register("ImgUri", typeof(string), typeof(WebImage), new PropertyMetadata("", OnImgUriChanged));        private string _ImgUri;        public ImageSource Source        {            get { return ImgShow.Source; }            set { ImgShow.SetValue(Image.SourceProperty, value); }        }        public Stretch Stretch        {            get { return ImgShow.Stretch; }            set { ImgShow.SetValue(Image.StretchProperty, value); }        }        public string ImgUri        {            get            {                return _ImgUri;            }            set            {                _ImgUri = value;                SetImgSource(_ImgUri);            }        }        void SetImgSource(string uri)        {            string cacheName = Path.Combine(CacheFolder, ParseUri(uri));            _imgSource = new BitmapImage();            _imgSource.ImageOpened += imgSource_ImageOpened;            if (IsolatedStorageFileHelper.FileExists(cacheName))            {                using (Stream stream = IsolatedStorageFileHelper.OpenFile(cacheName))                {                    _imgSource.SetSource(stream); ;                }                ImgShow.Visibility = System.Windows.Visibility.Visible;                gdWait.Visibility = System.Windows.Visibility.Collapsed;            }            else            {                _imgSource.DownloadProgress += imgSource_DownloadProgress;                _imgSource.ImageFailed += imgSource_ImageFailed;                _imgSource.UriSource = new Uri(uri, UriKind.Absolute);            }            ImgShow.Source = _imgSource;        }        void imgSource_ImageFailed(object sender, ExceptionRoutedEventArgs e)        {            _imgSource.ImageOpened -= imgSource_ImageOpened;            _imgSource.ImageFailed -= imgSource_ImageFailed;            _imgSource.DownloadProgress -= imgSource_DownloadProgress;        }        void imgSource_ImageOpened(object sender, RoutedEventArgs e)        {            ImgShow.Visibility = System.Windows.Visibility.Visible;            gdWait.Visibility = System.Windows.Visibility.Collapsed;            BitmapImage img = (BitmapImage)sender;            WriteableBitmap wb = new WriteableBitmap(img);            using (Stream stream = IsolatedStorageFileHelper.CreateFile(Path.Combine(CacheFolder, ParseUri(img.UriSource.AbsoluteUri))))            {                wb.SaveJpeg(stream, img.PixelWidth, img.PixelHeight, 0, 100);            }            _imgSource.ImageOpened -= imgSource_ImageOpened;            _imgSource.ImageFailed -= imgSource_ImageFailed;            _imgSource.DownloadProgress -= imgSource_DownloadProgress;        }        void imgSource_DownloadProgress(object sender, DownloadProgressEventArgs e)        {            rectProgress.Height = gdWait.ActualHeight * (e.Progress / 100.0);            tbProgress.Text = e.Progress.ToString();            _imgSource.DownloadProgress -= imgSource_DownloadProgress;        }        public WebImage()        {            InitializeComponent();        }        private static void OnImgUriChanged(DependencyObject obj, DependencyPropertyChangedEventArgs e)        {            WebImage img = obj as WebImage;            img.ImgUri = e.NewValue as string;        }        private string ParseUri(string uri)        {            return uri.Replace("://", "").Replace("/", "_");        }    }}

using System;using System.Collections.Generic;using System.IO.IsolatedStorage;using System.Linq;using System.Text;using System.Threading.Tasks;using System.Xml.Serialization;namespace WpDemo.Common{    public class IsolatedStorageFileHelper    {        private static IsolatedStorageFile _Store = null;        private static IsolatedStorageFile Store        {            get            {                if (_Store == null)                {                    _Store = IsolatedStorageFile.GetUserStoreForApplication();                }                return _Store;            }        }        public static void CreateFolder(string dir)        {            if (Store.DirectoryExists(dir))                return;            Store.CreateDirectory(dir);        }        public static void DeleteFolder(string dir)        {            if (Store.DirectoryExists(dir))                return;            Store.DeleteDirectory(dir);        }        public static void DeleteFile(string path)        {            if (!Store.FileExists(path))                return;            Store.DeleteFile(path);        }        public static IsolatedStorageFileStream CreateFile(string path)        {            string[] parts = path.Split('\\');            string dir = "";            for (int i = 0; i < parts.Length - 1; i++)            {                string part = parts[i];                dir = System.IO.Path.Combine(dir, part);                if (!Store.DirectoryExists(dir))                    Store.CreateDirectory(dir);            }            return Store.CreateFile(path);        }        public static bool FileExists(string path)        {            return Store.FileExists(path);        }        public static IsolatedStorageFileStream OpenFile(string path)        {            return Store.OpenFile(path, System.IO.FileMode.Open);        }        public static void SerializeObject(object obj, string path)        {            if (Store.FileExists(path))                Store.DeleteFile(path);            XmlSerializer xml = new XmlSerializer(obj.GetType());            using (var stream = CreateFile(path))            {                xml.Serialize(stream, obj);            }        }        public static T DeSerializeObject<T>(string path)        {            if (!Store.FileExists(path))                return default(T);            XmlSerializer xml = new XmlSerializer(typeof(T));            object obj = null;            using (var stream = OpenFile(path))            {                obj = xml.Deserialize(stream);            }            return (T)obj;        }    }}

用法如下:

xmlns:MyControl="clr-namespace:CloudWpDemo.Controls"

<StackPanel Grid.Column="0" Width="200">                                <MyControl:WebImage ImgUri="{Binding Img_url}" Margin="5,5,5,5"></MyControl:WebImage>                                <!--<Image Source="{Binding Img_url}"></Image>                                <TextBlock Text="{Binding Name}"></TextBlock>-->                            </StackPanel>

 我测试过蛮多次。。。。此控件挺好用的！！！希望对你的开发有用！！！！