How to connect to microsoft exchange online and retrieve info

gistfile1.cs

    public class ExchangePowerShell
    {
        public static PSCredential GetCredentials(string userName, string password)
        {
            var securePassword = new SecureString();
            Array.ForEach(password.ToCharArray(), securePassword.AppendChar);
            var cred = new PSCredential(userName, securePassword);

            return cred;
        }

        public static ExchangeUser GetMSOnlineUser(string email, string credUserName, string credPassword)
        {
            try
            {
                PSSnapInException exception = new PSSnapInException();
                Runspace runspace = RunspaceFactory.CreateRunspace();
                
                runspace.RunspaceConfiguration.AddPSSnapIn("Microsoft.Exchange.Transporter", out exception);
                
                var credentials = ExchangePowerShell.GetCredentials(credUserName, credPassword);
                
                runspace.Open();
                
                Pipeline pipeline = runspace.CreatePipeline();

                Command MsOnlineUserCmd = new Command("Get-MSOnlineUser");
                CommandParameter credentialParam = new CommandParameter("Credential", credentials);
                CommandParameter identityParam = new CommandParameter("Identity", email);
                MsOnlineUserCmd.Parameters.Add(credentialParam);
                MsOnlineUserCmd.Parameters.Add(identityParam);
                pipeline.Commands.Add(MsOnlineUserCmd);
                
                pipeline.Commands.Add("Out-String");

                Collection<PSObject> results = pipeline.Invoke();

                runspace.Close();

                StringBuilder stringBuilder = new StringBuilder();
                foreach (PSObject obj in results)
                {
                    stringBuilder.AppendLine(obj.ToString());
                }
                return null;
            }
            catch (PSSnapInException snapException)
            {
                return null;
            }
            catch (Exception exception)
            {
                return null;
            }

        }
   }