C＃字符串等于不能正常工作[关闭]

I get response string "true" from php file... but ,my function always return false ... here is piece of code

        public Boolean authorization(String korisnik, String zaporka) {
        using (var client = new WebClient())
        {
            var values = new NameValueCollection();
            values["korisnik"] = korisnik;
            values["zaporka"] = zaporka;

            var response = client.UploadValues("http://localhost/projectX/autorizacija.php", values);
            String responseString = Encoding.Default.GetString(response);
            System.Diagnostics.Debug.WriteLine(responseString);
            if (responseString.Equals("true"))
            {
                return true;
            }
            else
            {
                return false;
            }

        }

    }

Try:

if (responseString.Trim().Equals("true", StringComparison.InvariantCultureIgnoreCase))
{
  return true;
}
else
{
  System.Diagnostics.Debug.WriteLine(responseString);
  return false;
}

InvariantCultureIgnoreCase = compares strings in a linguistically relevant manner that ignores case Trim = remove whitespaces

And if false, check output value