HttpClient Post Request Method - C#

async static void PostRequest(string url)
{
    IEnumerable<KeyValuePair<string, string>> queries = new List<KeyValuePair<string, string>>()
            {
                new KeyValuePair<string, string>("query1", "number1"),
                new KeyValuePair<string, string>("query2", "number2")
            };
    HttpContent q = new FormUrlEncodedContent(queries);
    using (HttpClient client = new HttpClient())
    {
        using (HttpResponseMessage response = await client.PostAsync(url, q))
        {
            using (HttpContent content = response.Content)
            {
                string mycontent = await content.ReadAsStringAsync();
                HttpContentHeaders header = content.Headers;
                Console.WriteLine(mycontent);
            }
        }

    }
}