using System;

using System.Net;

using System.IO;

using System.Security.Cryptography.X509Certificates;

using System.Net.Security;

public class Program

{

    public static void Main()

    {

        string result = String.Empty;

​

        //string urlTypeForm = "https://api.typeform.io/v1/";

        string urlTypeForm = "https://api.typeform.com/v1/form/XbooY7?key=93fc605f3a549c9264c6ff575e29a4043e5b09ac";

        string chaveTypeForm = "93fc605f3a549c9264c6ff575e29a4043e5b09ac";

        var httpWebRequest = (HttpWebRequest)WebRequest.Create(urlTypeForm);

        httpWebRequest.ContentType = "application/json";

        httpWebRequest.Accept = "*/*";

        httpWebRequest.Method = "GET";

        //httpWebRequest.Headers.Add("X-API-TOKEN", "Basic " + chaveTypeForm);

        //Linha adicionada ao método para resolver o erro de certificado

        /*

        System.Net.ServicePointManager.ServerCertificateValidationCallback +=

        (se, cert, chain, sslerror) =>

        {

            return true;

        };  

        */

        var httpResponse = (HttpWebResponse)httpWebRequest.GetResponse();

        using (var streamReader = new StreamReader(httpResponse.GetResponseStream()))

        {

            result = streamReader.ReadToEnd();

        }

        Console.WriteLine(result);

    }

}