# Search for a virtual number using .NET SDK

Use this guide to create a .NET application for use with the Numbers API and search for an available Sinch virtual number.

Note:
Before you can get started, you need the following already set up:

- 
- [.NET 7.0 SDK](https://dotnet.microsoft.com/download) or later and a familiarity with how to create a new app.


Steps:
1. [Set up](#set-up-your-net-application) your .NET application.
2. [Search for an available virtual number](#search-for-an-available-virtual-number) for SMS, Voice or both.


# Sinch .NET SDK for Numbers API

The Sinch Numbers .NET SDK allows you to quickly interact with the Numbers API from inside your .NET applications.

## Set up your .NET application

1. Create a new folder where you want your app project. Then, open a terminal or command prompt to that location.
2. Create a new .NET console app with the following command:



```shell
dotnet new console
```

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
```


1. Open the `Program.cs` file in your project folder. Replace all of the code with the "Search for a virtual number" code.


Program.cs
// Use this code to search for available virtual numbers with the .NET SDK. 
using System.Text.Json;
using Sinch;
using Sinch.Numbers;
using Sinch.Numbers.Available.List;


var sinch = new SinchClient("YOUR_project_id",
                            "YOUR_access_key", 
                            "YOUR_access_secret");

var response = await sinch.Numbers.Available.List(new ListAvailableNumbersRequest
{
    RegionCode = "US",
    Type = Types.Local
});

Console.WriteLine(JsonSerializer.Serialize(response, new JsonSerializerOptions()
    {
        WriteIndented = true
    }));
### Modify your application

The code provided includes placeholder parameters. You'll need to update the parameters detailed in the following subsections with your values.

#### 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.

To start using the SDK, you need to initialize the main client class with your credentials from your Sinch [dashboard](https://dashboard.sinch.com).

Note:
For testing purposes on your local environment it's fine to use hardcoded values, but before deploying to production we strongly recommend using environment variables to store the credentials.


```cpp Initialize client
using Sinch;

var sinch = new SinchClient("YOUR_project_id",
                            "YOUR_access_key", 
                            "YOUR_access_secret");
```

You can also implement the client using ASP.NET dependency injection. `SinchClient` is thread safe, so it's fine to add it as a singleton:


```cpp Initialize client using dependency injection
builder.Services.AddSingleton<ISinchClient>(x => new SinchClient(
    builder.Configuration["YOUR_project_id"],
    builder.Configuration["YOUR_access_key"],
    builder.Configuration["YOUR_access_secret"]));
```

When finished, save the file.

### Build your project

Before executing your code, you must first compile your application. Execute the following command:


```shell
dotnet build
```

## Search for an available number

Now you can execute the code. Run the following command:


```shell
dotnet run
```

### Response

These steps should return a JSON list of numbers available to rent.


```json
{
  "availableNumbers": [
    {
      "phoneNumber": "+12089087284",
      "regionCode": "US",
      "type": "LOCAL",
      "capability": ["SMS"],
      "setupPrice": {
        "currencyCode": "USD",
        "amount": "0.00"
      },
      "monthlyPrice": {
        "currencyCode": "USD",
        "amount": "2.00"
      },
      "paymentIntervalMonths": 1
    }
  ]
}
```

## Next steps

Copy the `phoneNumber` you would like to use and [rent your virtual number using the Numbers API](/docs/numbers/getting-started/dotnet-sdk/rentandconfig).

## Additional resources

- Explore the [API specification](/docs/numbers/api-reference/numbers) to test more endpoints.
- Prefer a UI to search for a number? Follow the entire number searching and renting process [in the Sinch Build Dashboard](https://dashboard.sinch.com/numbers/buy-numbers).