Access HttpContent data while downloading a large file

Question

Hello,
for downloading large files methods such as ReadAsByteArrayAsync and ReadAsStreamAsync are inefficient because everything is being cached in memory and you can't access either the byte array or the stream until the await call returns (at this point the entire
file has been downloaded).
HttpClient client = new HttpClient();
Task<HttpResponseMessage> responseTask = client.GetAsync(new Uri("http://video.ch9.ms/ch9/f04f/87cd2a8d-cf52-4b80-bd97-b089e6b2f04f/308MicrosoftAnalyticsPlatformSystemM02_high.mp4"));
HttpResponseMessage response = await responseTask;
Task<byte[]> contentTask = response.Content.ReadAsByteArrayAsync();
byte[] content = await contentTask; // when this call returns the entire file has been downloaded and file data is finally accessible
Is there a more efficient method to download large files and also to be able to access file data while the download is still running?
Thx
Steve

Answer 1

and if you realllly wanna do it. i think you have to do something like this; but you will have to use a stream
HttpClientHandler handler = new HttpClientHandler();
HttpClient client = new HttpClient(handler);
var response = await client.GetAsync("http://video.ch9.ms/ch9/f04f/87cd2a8d-cf52-4b80-bd97-b089e6b2f04f/308MicrosoftAnalyticsPlatformSystemM02_high.mp4", HttpCompletionOption.ResponseHeadersRead);
var responseStream = await response.Content.ReadAsStreamAsync();
byte[] buf = new byte[512];
int bufSize;
while((bufSize = (await responseStream.ReadAsync(buf, 0, buf.Length))) > 0)
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