The request was aborted: Could not create SSL/TLS secure channel.

C# Code

ServicePointManager.Expect100Continue = true;
ServicePointManager.SecurityProtocol = SecurityProtocolType.Ssl3;
ServicePointManager.ServerCertificateValidationCallback = new RemoteCertificateValidationCallback(ValidateServerCertificate);

public static bool ValidateServerCertificate(object sender, X509Certificate certificate, X509Chain chain, SslPolicyErrors policyErrors)
{
            return true;
}

Salesforce APEX: Class variable/property are access dynamically

1.      Class  description

public class mobile
{
  public string SMS{get;set;}
  public string calling{get;set;}

}

2.      your  code to pick property value dynamically  

     mobile m =new mobile();
     m.SMS='SMS Test';
     m.calling='My Calling';

     String serialized = JSON.serialize(m); // object convert JSON string
      Map<String, Object> parameters = new Map<String, Object>();
      parameters = (Map<String, Object>) JSON.deserializeUntyped(serialized);
     
    string   fieldvalue=parameters.get( 'SMS');

   string   fieldvalue2=parameters.get(‘calling’);