flask request object port

Request.cs

namespace Foo {
    public class Request {
        HttpListenerContext context;
        Task<int> read_body;
        byte[] body = new byte[4096];
        public Request (HttpListenerContext ctx) {
            context = ctx;
            read_body = context.Request.InputStream.ReadAsync (body, 0, 4096);
        }
        public string path {
            get => context.Request.Url.PathAndQuery;
        }
        public IEnumerable<(string, string)> args {
            get => context.Request.Url.Query
                .Split ('&').Select ((query) => {
                    var x = query.Split ('=');
                    if (x.Length == 2)
                        return (
                            HttpUtility.UrlDecode (x[0]),
                            HttpUtility.UrlDecode (x[1])
                        );
                    return (x[0], null);
                });
        }
        public async Task WaitFinishAsync () {
            await read_body;
        }

        /// <<summary>
        /// warning: throws inner exception if present
        /// </summary>
        public bool IsCompleted {
            get {
                if (read_body.IsCompleted)
                    if (read_body.IsCompletedSuccessfully)
                        return true;
                    else throw read_body.Exception;
                return false;
            }
        }
        public IEnumerable<(string, string)> form {
            get => text.Split ('&').Select ((query) => {
                var x = query.Split ('=');
                if (x.Length == 2)
                    return (
                        HttpUtility.UrlDecode (x[0]),
                        HttpUtility.UrlDecode (x[1])
                    );
                return (x[0], null);
            });
        }
        public IEnumerable<(string, string)> headers {
            get => context.Request.Headers.AllKeys.Select (x =>
                     (x, string.Join (',', context.Request.Headers.GetValues (x)))
                );
        }
        public byte[] content {
            get => IsCompleted ? body : null;
        }
        public string text {
            get => IsCompleted ? Encoding.UTF8.GetString (body, 0, read_body.Result) : null;
        }
    }
}