Question

我从应用程序中的隔离存储设置加载图像路径。

    [DataMember]
    public string entryImage = "";

    [DataMember]
    public string EntryImage
    {
        get { return entryImage; }
        set { entryImage = value; }
    }

使用帮助程序类将图像存储到隔离的存储文件中。

    public static void SaveImage(Stream imageStream, string directory, string filename)
    {
        try
        {
            string path = System.IO.Path.Combine(directory, filename);

            using (IsolatedStorageFile isoStore = IsolatedStorageFile.GetUserStoreForApplication())
            {
                if (!isoStore.DirectoryExists(directory)) isoStore.CreateDirectory(directory);

                using (var writeStream = isoStore.CreateFile(path))
                {
                    byte[] buffer = new byte[32768];
                    while (true)
                    {
                        int read = imageStream.Read(buffer, 0, buffer.Length);

                        if (read <= 0)
                            return;
                        writeStream.Write(buffer, 0, read);
                    }
                }
            }

        }
        // Catch exception if unable to save the image
        catch (Exception ex)
        {
            MessageBox.Show(ex.Message);
        }
    }

这是我将imagepath存储到observablecollection的部分

        MyDiaryItem _saveItems = new MyDiaryItem();
        _saveItems.EntryNotes = InputText.Text;
        _saveItems.EntryDate = date.ToString();
        _saveItems.EntryImage = AppHelper.ImageDirectory + AppSettings.ImageFilename;

MyDiaryItem是可观察集合的地方

 public ObservableCollection<MyDiaryItem> diaryItems = null;

隔离存储保存和加载

         void LoadSettings()
    {
        if (settings.Contains("DiaryItems"))
        {
            diaryItems = new ObservableCollection<MyDiaryItem>((List<MyDiaryItem>)settings["DiaryItems"]);
        }
    }

    void SaveSettings()
    {
        //settings["DiaryItems"] = diaryItems.ToList();
        if (diaryItems.ToList() != null)
        {
            settings.Clear();
            settings.Add("DiaryItems", diaryItems.ToList());
            settings.Save();
        }
    }

这是图像源的xaml代码

            <ListBox toolkit:TiltEffect.IsTiltEnabled="true" Name="AllEntriesList"
                     Margin="0,0,-12,0"
                     SelectionChanged="AllEntriesList_SelectionChanged">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <StackPanel Orientation="Horizontal" Margin="0,0,0,17">
                            <Image Source="{Binding EntryImage}" Height="100" Width="100" Stretch="Fill" Margin="12,0,9,0" />
                            <StackPanel Margin="0,0,0,17" Width="350" Height="Auto">
                                <TextBlock Text="{Binding EntryLocation}" TextWrapping="Wrap" Style="{StaticResource PhoneTextLargeStyle}" />
                                <TextBlock Text="{Binding EntryNotes}" TextWrapping="Wrap" Style="{StaticResource PhoneTextNormalStyle}" />
                                <TextBlock Text="{Binding EntryDate}" TextWrapping="Wrap" Style="{StaticResource PhoneTextSubtleStyle}" />
                            </StackPanel>
                        </StackPanel>
                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>

我想了解如何使用从隔离存储中重新获取的imagepath来显示diaryitems列表中的图像。

我在我的OnNavigatedTo函数中加载了所有的diaryitems。

AllEntriesList.ItemsSource = app.diaryItems;

我可以在diaryItems列表中看到正确填充的图像名称。我想在diaryItems列表中显示图像。怎么做？

Answer 1

 <Image Source="{Binding EntryImage}" Height="100" Width="100" Stretch="Fill" Margin="12,0,9,0" />

您正在将字符串绑定到图像源。尝试将其绑定到BitmapSource
您可以轻松地从流中获取BitmapSource。例如：

 BitmapSource CreateSource(Stream stream)
 { 
     return source = PictureDecoder.DecodeJpeg(stream);
 }

将图像从孤立存储加载到可观察集合不工作

1 个答案: