# Creating an appointment reminder app with .NET SDK

## Set up your .NET application

1. Navigate to the directory in which you'd like to store your app project.
2. Create a new folder called `sinch_appointment_reminder`.
3. Open a terminal or command prompt to that location.
4. Create a new .NET MVC app with the following command:



```shell
dotnet new mvc
```

### Installing the SDK

The easiest way to install the SDK is using the [`dotnet` CLI](https://learn.microsoft.com/en-us/dotnet/core/install/windows?tabs=net70):

1. Open a command prompt or terminal to the local repository folder.
2. Execute the following command:

```shell
dotnet add package Sinch
```


### Client information

When using the SDK, you must initialize the client.

Before initializing a client using this SDK, you'll need three pieces of information:

- Your Project ID
- An access key ID
- An access key Secret


These values can be found on the [<b>Access Keys</b>](https://dashboard.sinch.com/settings/access-keys) page of the Sinch Build Dashboard. You can also [create new access key IDs and Secrets](https://community.sinch.com/t5/Conversation-API/How-to-get-your-access-key-for-Conversation-API/ta-p/8120), if required.

Note
If you have trouble accessing the above link, ensure that you have gained access to the [Conversation API](https://dashboard.sinch.com/convapi/overview) by accepting the corresponding terms and conditions.

You'll add these values to the file described in the next section (along with others).

#### Setting the environment variables

Your app stores information such as your Sinch credentials as key-value pairs in the `appsettings.Development.json` file.  This is much more flexible and secure than simply hardcoding them.

br
To set up your `appsettings.Development.json` file:

1. Open the `appsettings.Development.json` file.
2. Paste the following JSON body into your `appsettings.Development.json` file.

```json
"Sinch":{
    "key_id":"",
    "key_secret":"",
    "project_id":"",
    "country_code_eu": "",
    "country_code_us": "",
    "from_number": "",
    "sms_region":""
},
```
3. Populate the fields in the file with your own values. Refer to the table below for guidance:


| Field | Description |
|  --- | --- |
| `key_id` | Your access key ID, used for authentication. Refer to the [Client information](#client-information) section for more information. |
| `key_secret` | Your access key secret, used for authentication. Refer to the [Client information](#client-information) section for more information. |
| `project_id` | Your project ID. Refer to the [Client information](#client-information) section for more information. |
| `country_code_eu` | If you live in the EU or UK, this is the country code of your home country. For example the UK country code is `+44`. |
| `country_code_us` | If you live in the US, this is the country code of your home country. For the US, it's `+1`. |
| `from_number` | Any number you've assigned to your Sinch account. Find the number on your Customer [Dashboard](https://dashboard.sinch.com/sms/api/rest) by clicking the service plan ID link and scrolling to the bottom of the page. |
| `sms_region` | The region in which you would like to send SMS messages. Either `us` or `eu`. |


### Modifying the `Program.cs` file

In .NET, `Program.cs` has the job of setting your application up and running it. The dependencies your application needs are created as *services*. These services will be fed into a Controller using *Dependency Injection*. The SDK client is initialized and added to Services as a *singleton*, meaning there can only be one instance of it.

br
Open `Program.cs` and replace the contents with the following code:


```csharp
using Sinch;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
builder.Services.AddControllersWithViews();


builder.Services
      .AddMvc();
builder.Services.AddSingleton<ISinchClient>(_ => new SinchClient(
    builder.Configuration["Sinch:project_id"],
     builder.Configuration["Sinch:key_id"],
    builder.Configuration["Sinch:key_secret"],

                         // ensure you set the SMS region. 
                         options =>
                         {
                             options.SmsRegion = Sinch.SMS.SmsRegion.Us;
                             options.LoggerFactory = LoggerFactory.Create(config => { config.AddConsole(); });
                             options.HttpClient = new HttpClient();
                         }));

var app = builder.Build();

// Configure the HTTP request pipeline.
if (!app.Environment.IsDevelopment())
{
    app.UseExceptionHandler("/Home/Error");
    // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts.
    app.UseHsts();
}

app.UseHttpsRedirection();
app.UseStaticFiles();

app.UseRouting();

app.UseAuthorization();

app.MapControllerRoute(
    name: "default",
    pattern: "{controller=Home}/{action=Index}/{id?}");

app.Run();
```