[WP7]由檔案路徑讀取IsolatedStarage的圖檔

using System;
using System.IO;
using System.IO.IsolatedStorage;
using System.Windows.Data;
using System.Windows.Media.Imaging;
using Microsoft.Phone;
namespace XXXX.Common
{
    public class FilePathToImageConverter : IValueConverter
    {
        private static IsolatedStorageFile isf = IsolatedStorageFile.GetUserStoreForApplication();
        public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            string path = value as string;
            if (String.IsNullOrEmpty(path))
                return null;
            if ((path.Length > 9) && (path.ToLower().Substring(0, 9).Equals("isostore:")))
            {
                using (IsolatedStorageFileStream isfs = isf.OpenFile(path.Substring(9), FileMode.Open, FileAccess.Read))
                {
                    WriteableBitmap wb = PictureDecoder.DecodeJpeg(isfs, 80, 50);
                    return wb;                    
                }
            }
            else
            {
                BitmapImage bi = new BitmapImage(new Uri(path, UriKind.Relative));
                return bi;
            }
        }
        public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
        {
            throw new NotImplementedException();
        }
    }
}

可以這樣使用

<common:FilePathToImageConverter x:Key="FilePathToImageConverter" />
<Image x:Name="Image1" Source="{Binding ImageSource,Converter={StaticResource FilePathToImageConverter}}" Width="80" Height="50" ></Image>