如何在IsolatedStorage中存储和获取图像？

Question

我希望能够在IsolatedStorage中保存图像，然后得到它。

为此，我编写了一个助手，我想在我的应用程序中从任何地方访问它：

用于创建图像的：

public static void SaveImage(Stream image, string name)
{
    try
    {
        IsolatedStorageFile isolatedStorage = IsolatedStorageFile.GetUserStoreForApplication();

        if (!isolatedStorage.DirectoryExists("MyImages"))
        {
            isolatedStorage.CreateDirectory("MyImages");
        }

        var filePath = Path.Combine("MyImages", name + ".jpg");

        using (IsolatedStorageFileStream fileStream = new IsolatedStorageFileStream(filePath, FileMode.Create, isolatedStorage))
        {
            StreamWriter sw = new StreamWriter(fileStream);
            sw.Write(image);
            sw.Close();
        }
    }
    catch (Exception ex)
    {
        throw new Exception("failed");
    }
}

和再次获得那个图像：

public static BitmapImage Get(string name)
{
    try
    {
        IsolatedStorageFile isolatedStorage = IsolatedStorageFile.GetUserStoreForApplication();

        var filePath = Path.Combine("MyImages", name + ".jpg");

        using (IsolatedStorageFileStream fileStream = new IsolatedStorageFileStream(filePath, FileMode.Open, isolatedStorage))
        {
            BitmapImage image = new BitmapImage();
            image.SetSource(fileStream);
            return image;
        }
    }
    catch (Exception ex)
    {
        throw new Exception("failed");
    }
}

当我试图设置image源代码时，会出现以下错误消息：

找不到组件。(HRESULT例外: 0x88982F50)

Answer 1

假设您在WMAppManifest.xml下拥有正确的功能，那么您需要的是：

public static void SaveImage(Stream image, string name)
{

    var bitmap = new BitmapImage();
    bitmap.SetSource(attachmentStream);
    var wb = new WriteableBitmap(bitmap);
    var temp = new MemoryStream();
    wb.SaveJpeg(temp, wb.PixelWidth, wb.PixelHeight, 0, 50);

    using (var myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication())
    {
        if (!myIsolatedStorage.DirectoryExists("MyImages"))
        {
            myIsolatedStorage.CreateDirectory("MyImages");
        }

        var filePath = Path.Combine("MyImages", name + ".jpg");

        using (IsolatedStorageFileStream fileStream = new IsolatedStorageFileStream(filePath, FileMode.Create, myIsolatedStorage))
        {
            fileStream.Write(((MemoryStream)temp).ToArray(), 0, ((MemoryStream)temp).ToArray().Length);
            fileStream.Close();
        }
    }
}

这样可以将图像作为jpeg存储到所需的目录中。如果没有，请确保create目录和Path.Combine()方法被正确使用。