TelnyxSharp

A comprehensive .NET SDK for the Telnyx API, providing seamless integration with Telnyx telephony services including SMS/MMS messaging, voice calls, number management, WebRTC, and more. Built exclusively for .NET 9 with full async support and built-in rate limiting.

Prerequisites

• .NET 9.0 or later (This SDK targets .NET 9 exclusively)
• A Telnyx account with API credentials

Installation

To install the TelnyxSharp SDK, you can use the NuGet package manager:

dotnet add package TelnyxSharp

Or via the NuGet Package Manager Console:

Install-Package TelnyxSharp

Usage

Direct Initialization

Here's a quick example to get you started:

using TelnyxSharp;
using TelnyxSharp.Messaging.Models.Messages.Requests;
using TelnyxSharp.Messaging.Models.Messages.Responses;

var apiKey = "YOUR_API_KEY";
var client = new TelnyxClient(apiKey);

// Create a message request
var messageRequest = new SendMessageRequest
{
    From = "+1234567890",
    To = new List<string> { "+0987654321" },
    Text = "Hello from TelnyxSharp!"
};

// Send the message
SendMessageResponse response = await client.Messages.Send(messageRequest);

Console.WriteLine($"Message sent with ID: {response.Id}");

Using Dependency Injection

For applications using Microsoft.Extensions.DependencyInjection, you can register the Telnyx client in your service collection:

using Microsoft.Extensions.DependencyInjection;
using TelnyxSharp;

// In your Startup.cs or Program.cs
services.AddTelnyxClient(options =>
{
    options.ApiKey = "YOUR_API_KEY";
});

Then inject ITelnyxClient into your classes:

public class MessagingService
{
    private readonly ITelnyxClient _telnyxClient;

    public MessagingService(ITelnyxClient telnyxClient)
    {
        _telnyxClient = telnyxClient;
    }

    public async Task SendMessage(string to, string text)
    {
        var messageRequest = new SendMessageRequest
        {
            From = "+1234567890",
            To = new List<string> { to },
            Text = text
        };

        var response = await _telnyxClient.Messages.Send(messageRequest);
        Console.WriteLine($"Message sent with ID: {response.Id}");
    }
}

This approach is recommended for ASP.NET Core applications and other scenarios where you want to manage the lifetime of the client through dependency injection.

Features

• 📱 SMS/MMS Messaging - Send and receive text and multimedia messages
• 📞 Voice Calls - Programmable voice capabilities
• 🔢 Number Management - Phone number ordering, porting, and configuration
• 🌐 WebRTC - Real-time communication support (via Blazor components)
• 📊 10DLC Campaigns - Support for A2P messaging campaigns
• 🔍 Number Lookup - Carrier and caller ID information
• 📝 Call Detail Records - Access and search call records
• ⚡ Built-in Rate Limiting - Automatic retry with exponential backoff
• 🔄 Full Async Support - All operations support async/await patterns
• 💉 Dependency Injection Ready - First-class DI support for modern .NET applications

Requirements

• .NET 9.0 SDK or later
• Compatible with:
  • ASP.NET Core 9.0+
  • Blazor Server/WebAssembly 9.0+
  • Console Applications
  • Azure Functions
  • Any .NET 9.0+ compatible platform

Contributing

We welcome contributions! Please read our contributing guidelines to get started.

License

This project is licensed under the MIT License - see the LICENSE file for details.