Creating an appointment reminder app with .NET SDK
Creating the application
To function, your code needs to have the ability to validate input data and send texts. It also needs to display different pages depending on whether a user is inputting an appointment or has already submitted the appointment details. The controller contains the business logic of your application.
In theControllers folder, create a file called AppointmentController.cs. Then, copy the code displayed on the right panel of this page and paste the contents into the file. We'll step through each section of code below.Importing the SDK
This code imports the SDK functionality your app needs to update a group and send a reply. It also specifies the namespace the Controller is in:
using System.Diagnostics;
using Microsoft.AspNetCore.Mvc;
using sinch_appointment_reminder.Models;
using Sinch;
using System.Text.Json;
namespace sinch_appointment_reminder.Controllers;
public class AppointmentController : Controller
{
}The AppointmentController class
Now let's review the class members and constructor. Take a look at the following code, which defines the AppointmentController class:public AppointmentController(ISinchClient sinchClient, ILogger<AppointmentController> logger, IConfiguration configuration)
{
_logger = logger;
_sinchClient = sinchClient;
Configuration = configuration;
}AppointmentController members. This includes the SDK client object, which will be used to send SMS messages. There is also a configuration object for reading config values and logger object for debugging.The RemindPatient method
Now we'll review the RemindPatient method:public async void RemindPatient(string to, string message, DateTime reminder_datetime)
{
var response = await _sinchClient.Sms.Batches.Send(new Sinch.SMS.Batches.Send.SendTextBatchRequest
{
Body = message,
From = Configuration["Sinch:from_number"],
To = new List<string> { to },
SendAt = reminder_datetime,
DeliveryReport = Sinch.SMS.DeliveryReport.None
});
Console.WriteLine(JsonSerializer.Serialize(response, new JsonSerializerOptions()
{
WriteIndented = true
}));
}SendAt parameter. Because the Sinch SMS REST API has message scheduling built in, it's a one-stop shop for any application that requires sending SMS messages at particular times. This reduces the amount of dependencies you need. Even better, it means you don't need your app to be running all the time!In addition to
SendAt, the send method has a number of other parameters, including message expiry and delivery reports. These are available on the REST API reference.General controller methods
We're now going to review the methods for our controller:
public async Task<IActionResult> Index()
{
return RedirectToAction(nameof(Submit));
}
public async Task<IActionResult> Submit()
{
return View();
}These methods implement the application's functionality and shunt users to the correct page at each point on their journey.
- The first method redirects from the root URL. This means that users can simply type
http://localhost:<port>/appointmentand they will be taken to the appointment scheduling form athttp://localhost:<port>/appointment/submit. - The second method displays the appointment scheduling form.
The Submit post method
Now let's review the Submit post method:[HttpPost]
public IActionResult Submit(string patient, string doctor, string phone, DateTime appointment_date, DateTime appointment_time)
{
DateTime appointment_datetime = new DateTime(appointment_date.Year, appointment_date.Month, appointment_date.Day, appointment_time.Hour, appointment_time.Minute, appointment_time.Second);
TempData["appointment_datetime"] = appointment_datetime;
TempData["patient"] = patient;
TempData["doctor"] = doctor;
TempData["phone"] = phone;
var now = DateTime.Now;
DateTime reminder_datetime = appointment_datetime.AddHours(-2).ToUniversalTime();
if (now.AddHours(2.08333) > appointment_datetime)
{
return RedirectToAction(nameof(Index));
}
string country_code = "+1";
if (Configuration["Sinch:sms_region"] == "eu")
{
country_code = Configuration["Sinch:country_code_eu"];
}
string to = country_code + phone;
string message = "Hi " + patient + ", you have a Sinch Hospital appointment with Dr " + doctor + " scheduled for " + appointment_datetime;
RemindPatient(to, message, reminder_datetime);
return RedirectToAction(nameof(Success));
}remindPatient. Once a confirmation message is sent, the user is redirected to the success page.This method also contains validation to make sure any appointment is booked at least a couple of hours into the future. This also stops users from accidently booking an appointment in the past.
The Sinch SDK requires phone numbers to have a country code, so the code checks the SMS region and adds a US/EU country code to the phone number.
Rendering the success page
The final route path renders the success page:
public IActionResult Success()
{
return View();
}Congratulations! That's the core of your application completed.
