An asynchronous module or handler completed while an asynchronous
operation was still pending.

public async void Put(int id,HttpRequestMessage request)
    {
        if (!Request.Content.IsMimeMultipartContent())
            throw new InvalidOperationException();

        var provider = new MultipartMemoryStreamProvider();
        await Request.Content.ReadAsMultipartAsync(provider);

        var file = provider.Contents.First();
        var filename = file.Headers.ContentDisposition.FileName.Trim('\"');
        var buffer = await file.ReadAsByteArrayAsync();
        var stream = new MemoryStream(buffer);

        using (var s = new StreamReader(stream))
        {
            saveFile.Execute(id,s);
        }
    }

只要我正在流式传输数据,我就会接受其他解决方案.我是新手等待和异步,我可能犯了一个基本错误.有任何想法吗？