用HttpClient替换HttpWebRequest

Question

Due to this reason, https://github.com/dotnet/corefx/issues/11873#issuecomment-470611032

I trying to replace HttpWebRequest with HttpClient

HttpWebRequest wr = (HttpWebRequest)WebRequest.Create(url);
wr.AllowWriteStreamBuffering = false;

using (var requestStream = await wr.GetRequestStreamAsync().ConfigureAwait(false))
{
    await this.ZipFilesIntoStream(fileEntries, requestStream).ConfigureAwait(false);
}

And I cannot find any guide on how to get the stream with HttpClient.

using (var memoryStream = new MemoryStream())
using (var requestStream = await wr.GetRequestStreamAsync().ConfigureAwait(false))
{
    await HttpClient.PostAsync(url, new StreamContent(memoryStream)
    {
    }).ConfigureAwait(false);

    await this.ZipFilesIntoStream(fileEntries, requestStream).ConfigureAwait(false);
}

Answer 1

The code tries to use HttpClient as if it were HttpWebRequest. An HttpClient doesn't represent a request though. It's a class that executes different HTTP methods. The contents should be prepared before calling PostAsync , GetAsync or the generic SendAsync

I assume that ZipFilesIntoStream packages files into a stream. Since a MemoryStream is also available, it should use it as its storage :

using (var memoryStream = new MemoryStream())
{
    await ZipFilesIntoStream(fileEntries, memoryStream);
    memoryStream.Position=0;
    await client.PostAsync(url, new StreamContent(memoryStream));
}