Windows 8.1將xaml以字符串形式保存InkManager

Question

我正在嘗試將用鉛筆繪制的內容保存為字符串，然后通過SaveAsync（）方法將其保存到IOutputStream中，然后使用AsStreamForWrite（）方法將此IOutputStream轉換為流，從這一點出發，很好，但是如果使用例如以下代碼塊，那么在這部分之后我會遇到很多問題：

  using (var stream = new MemoryStream())
                {
                    byte[] buffer = new byte[2048]; // read in chunks of 2KB
                   int bytesRead = (int)size;
                    while (bytesRead < 0)
                    {
                        stream.Write(buffer, 0, bytesRead);

                    }
                    byte[] result = stream.ToArray();
                    // TODO: do something with the result
                }

我得到這個例外

"Offset and length were out of bounds for the array or count is greater than the number of elements from index to the end of the source collection." 

或者如果我嘗試使用InMemoryRandomAccessStream將流轉換為圖像，如下所示：

 InMemoryRandomAccessStream ras = new InMemoryRandomAccessStream();
                await s.CopyToAsync(ras.AsStreamForWrite());

我的InMemoryRandomAccessStream變量的大小始終為零。

也嘗試過

StreamReader.ReadToEnd();

但它返回一個空字符串。

Answer 1

在這里找到答案：

http://social.msdn.microsoft.com/Forums/windowsapps/en-US/2359f360-832e-4ce5-8315-7f351f2edf6e/stream-inkmanager-strokes-to-string

private async void ReadInk(string  base64)
{
if (!string.IsNullOrEmpty(base64))
{
    var bytes = Convert.FromBase64String(base64);

    using (var inMemoryRAS = new InMemoryRandomAccessStream())
    {
        await inMemoryRAS.WriteAsync(bytes.AsBuffer());
        await inMemoryRAS.FlushAsync();
        inMemoryRAS.Seek(0);

        await m_InkManager.LoadAsync(inMemoryRAS);

        if (m_InkManager.GetStrokes().Count > 0)
        {
            // You would do whatever you want with the strokes
            // RenderStrokes(); 
        }
    }
}
}