how to decompress gzip in httpclient response in c#?

We can use enum DecompressionMethods as:

public async Task<string> GetResponseString(string text)
    {
       var clientHandler = new HttpClientHandler() { AutomaticDecompression = DecompressionMethods.GZip | DecompressionMethods.Deflate };
       var client = new HttpClient(clientHandler);

        var parameters = new Dictionary<string, string>();
        parameters["text"] = text;

        var response = await httpClient.PostAsync(BaseUri, new FormUrlEncodedContent(parameters));
        var contents = await response.Content.ReadAsStringAsync();

        return contents;
    }

Package:

System.Net.Http

For the compression of response content, general Web servers (such as IIS) provide built-in support, just need to include Accept-Encoding: gzip, deflate in the request header, client browser and HttpClient provide built-in decompression support. Following are the code to enable this compression in HttpClient is as follows:

var httpClient = new HttpClient(new HttpClientHandler { AutomaticDecompression = 
    System.Net.DecompressionMethods.GZip | System.Net.DecompressionMethods.Deflate });