wp7,IsolatedStorageFile保存和读取png图片

保存图片至IsolatedStorage：

private void btnSave_Click(object sender, RoutedEventArgs e)
        {
            WebClient wc = new WebClient();
            wc.OpenReadCompleted += new OpenReadCompletedEventHandler(wc_OpenReadCompleted);
            wc.OpenReadAsync(new Uri("http://php.weather.sina.com.cn/images/yb3/180_180/qing_0.png", UriKind.RelativeOrAbsolute));
        }
        void wc_OpenReadCompleted(object sender, OpenReadCompletedEventArgs e)
        {
            IsolatedStorageFile myStore = IsolatedStorageFile.GetUserStoreForApplication();
            myStore.CreateDirectory("Images");
            if (myStore.FileExists("Images"))
            {
                myStore.DeleteFile("Images");
            }

           

            //先读取图片流，再把图片保存成png格式：

            byte[] _imgBytes = new byte[e.Result.Length];
            e.Result.Read(_imgBytes,0,_imgBytes.Length);
            using (IsolatedStorageFile storage = IsolatedStorageFile.GetUserStoreForApplication())
            {
                using (Stream stream = storage.OpenFile("Images/sun.png", FileMode.Create))
                {
                    stream.Write(_imgBytes, 0, _imgBytes.Length);
                    MessageBox.Show("图片存储成功！");
                }
            }
        }

      IsolatedStorage中读取图片（和jpg读取图片一样）：

        private void btnRead_Click(object sender, RoutedEventArgs e)
        {
            BitmapImage bi = new BitmapImage();
            using (IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication())
            {
                using (IsolatedStorageFileStream fileStream = myIsolatedStorage.OpenFile("Images/sun.png", FileMode.Open, FileAccess.Read))
                {
                    bi.SetSource(fileStream);
                    this.imgPic.Height = bi.PixelHeight;
                    this.imgPic.Width = bi.PixelWidth;
                }
            }
            this.imgPic.Source = bi;
        }

 

参考自：http://www.itivy.com/wp7/archive/2011/11/17/windows-phone-save-and-load-image.html