从IsolatedStorage加载保存的图像时发生System.InvalidOperationException

Question

I have found a class from the link ImageCaching but when i load from isolated storage i got an exeption "System.InvalidOperationException"

here is my code

 public static object DownloadFromWeb(Uri imageFileUri)
    {
        WebClient m_webClient = new WebClient();                                //Load from internet
        BitmapImage bm = new BitmapImage();

        m_webClient.OpenReadCompleted += (o, e) =>
        {
            if (e.Error != null || e.Cancelled) return;
            WriteToIsolatedStorage(IsolatedStorageFile.GetUserStoreForApplication(), e.Result, GetFileNameInIsolatedStorage(imageFileUri));
            bm.SetSource(e.Result);
            e.Result.Close();
        };
        m_webClient.OpenReadAsync(imageFileUri);
        return bm;
    }

    public static object ExtractFromLocalStorage(Uri imageFileUri)
    {
        byte[] data;
        string isolatedStoragePath = GetFileNameInIsolatedStorage(imageFileUri);       //Load from local storage
        if (null == _storage)
        {
             _storage = IsolatedStorageFile.GetUserStoreForApplication();
        }
        using (IsolatedStorageFileStream sourceFile = _storage.OpenFile(isolatedStoragePath, FileMode.Open, FileAccess.Read))
        {


            // Read the entire file and then close it
            sourceFile.Read(data, 0, data.Length);
            sourceFile.Close();
           BitmapImage bm = new BitmapImage();
            bm.SetSource(sourceFile);///here got the exeption 
            return bm;

        }

    }

so that i can't set the image.

Answer 1

I'm using the converter you mentioned and it works but you modified the method.

Your ExtractFromLocalStorage method isn't the same. You close your stream before to use it with the SetSource method.

Here is the original method code:

 private static object ExtractFromLocalStorage(Uri imageFileUri)
    {
        string isolatedStoragePath = GetFileNameInIsolatedStorage(imageFileUri);       //Load from local storage
        using (var sourceFile = _storage.OpenFile(isolatedStoragePath, FileMode.Open, FileAccess.Read))
        {
            BitmapImage bm = new BitmapImage();
            bm.SetSource(sourceFile);
            return bm;
        }
    }