ASP.NET Core Identity is a membership system that adds user sign in and user management functionality to ASP.NET Core apps. It includes many features out of the box and has basic support for storing a phone number for a user. By default, ASP.NET Core Identity doesn't try to verify ownership of phone numbers, but you can add that functionality yourself by integrating Twilio’s identity verification features into your application.

In this post you’ll learn how you can prove ownership of a phone number provided by a user using Twilio Verify in an ASP.NET Core application using Razor Pages. This involves sending a code in an SMS message to the provided phone number. The user enters the code received and Twilio confirms whether it is correct. If so, you can be confident the user has control of the provided phone number.

You typically only confirm ...

Service-to-service communication is becoming more and more common, but we know the network has never been reliable and that other people's code has bugs. Packets are lost, exceptions are thrown, and requests fail; it will happen to your application—to all applications!
Using the Polly Resilience Framework you can easily retry a failed request, no messy for loops or try catches needed. Just a few lines of code and your applications will never be the same!

This post shows how to make reliable requests to an unreliable "remote" service with almost no overhead.

You’ll start with a “remote” Web API application that returns errors 75% of the time. Then you’ll build a “local“ Web API application that calls the remote one (of course receiving errors three quarters of the time).

Finally, you will add Polly to the “local” application to perform retires on failed requests. With a few ...

I love Bing Image of the day, it always makes me smile! I also love dogs, so I thought why not combine the two and create an app that sends a daily dog picture via WhatsApp.

This post will take you through all the steps to create an azure scheduled function in C#, make a call to the Dog API to retrieve a photo and then send the returned image to a number via the Twilio API for WhatsApp.

This post assumes some base knowledge of C# and RESTful APIs.

To get started, we will need:

• A Twilio account (sign up for a free Twilio account here)
• The WhatsApp Sandbox Channel installed in your account (go through this process to activate the sandbox)
• An Azure Account (sign up for free here)

Create an Azure Function

From the Azure portal, click the Create a resource button, found at the top of ...

An apt business use for both Twilio SMS and Twilio Sendgrid would be for customer enquiries on a website.  Using C# and .NET Core 2.2 we will build an app that receives an SMS, takes the from number and the message body and send out an email using Twilio SendGrid.

To get started with this project you will need the following:

• A Twilio account (sign up for a free Twilio account here)
• A Twilio SMS-enabled number
• The .NET Core 2.2 SDK and runtime
• A Twilio SendGrid account (sign up for free here)
• A SendGrid API Key
• Visual Studio Code or similar code editor or IDE

Creating the project

We are going to use the WebApi template project that comes with the .NET Core SDK, as a starting point.

From the command line, navigate to the location you wish to create the new application. Use the following command to ...

When the WhatsApp API for Twilio launched last year it only supported text.

Not anymore!

The WhatsApp API for Twilio now supports media, including images and files.  

So let's build an app that receives an image from WhatsApp, processes the image using one of the many options available on the Pho.to API and then returns the processed image.

What we'll need to get started.

• A Twilio account (sign up for a free Twilio account here)
• The .NET Core 2.2 SDK and runtime
• The WhatsApp Sandbox Channel installed in your account (go through this process to activate the sandbox)
• A developer account on the Pho.to API
• Visual Studio Code or similar code editor or IDE

Create a new folder for your project and navigate into it.

Once in your new folder, we can make a new .NET Core WebAPI project using the command below ...

Realtime user interaction is a great way to enhance the communication and collaboration capabilities of a web application. Video chat is an obvious choice for sales, customer support, and education sites, but how can you quickly implement it? Twilio Programmable Video enables you to efficiently add robust video chat to your applications, whether you are using a JavaScript Model-View-Controller framework like Angular or server-side templates.

This post will show you how to create a video chat application using the Twilio JavaScript SDK in your Angular single page application (SPA) and the Twilio SDK for C# and .NET in your ASP.NET Core server code. You’ll build the interactions required to create and join video chat rooms, and to publish and subscribe to participant audio and video tracks.

Prerequisites to a Angular and ASP.NET Core Video App

You’ll need the following technologies and tools to build the video ...

ASP.NET Core Identity is a membership system that adds login and user functionality to ASP.NET Core apps. It includes many features out of the box and has basic support for storing a phone number for a user. You can improve the robustness of ASP.NET Core’s phone number validation and provide a better user experience by integrating Twilio’s telephony features in your application.

By default the phone number in ASP.NET Core Identity is validated with a regular expression, but that's too basic to confirm whether the number is really valid, whether it includes the country dialling code, or whether it can receive SMS messages. You could implement improved validation using the library libphonenumber-csharp, as described in a previous Twilio blog post. Alternatively you could use various Twilio APIs to thoroughly validate the phone number, lookup details about the number (such as carrier or type), and ...

ASP.NET Core is built with first-class support for dependency injection (DI). It's used heavily by the framework, but you can also use it with your own classes. The Twilio C# helper libraries are largely static, so you don't have to use DI, but sometimes you might want to. For example, you might want to create a custom TwilioRestClient that uses the HttpClientFactory features of .NET Core 2.1. In this post, I describe how to create a custom ITwilioRestClient, register it with the ASP.NET Core DI container, and inject it into a web API controller, so you can use it to send an SMS.

Prerequisites

To follow along with this post you'll need:

• A Twilio account (sign up for a free Twilio account here)
• .NET Core 2.1 SDK (version 2.1.300 or greater)
• VS Code, Visual Studio, or other editor
• Postman for testing your API

You ...

As technology expands the reach of our products and services it’s important for us to create content to suit users from all over the world. As we primarily use Latin characters for programming, creating content for languages like Japanese or Arabic that have a different alphabet is not as easy as typing them on a standard keyboard. This post will show you how to send non-Latin characters, including emoji, in text messages with C# and Twilio Programmable SMS.

Prerequisites

You should have the following tools installed to complete the program described in this post:

• Windows 7 or Windows 10
• Basic knowledge of C# and .NET
• Visual Studio 2017 or Visual Studio Code
• Microsoft .NET Core SDK, which includes the .NET Runtime

Why UTF-8?

The problem started when people realized that the character encoding standard of the time, ASCII, needed to be extended to accommodate the alphabets of other languages ...

Will you need an umbrella today? Don't know? That's easy to fix by looking out the window or by using Azure Functions and its Twilio SMS output binding. In this post, I'll show you how with just a few lines of code you can have a text message arrive each morning which lets you know if it might rain that day.

You can build along with me by signing up for free Azure and free Twilio accounts.

Create an Azure Function

We'll start by creating a new Azure Function App in the Azure Portal.

Once created continue configuring the Function App by adding environment variables to hold our Twilio credentials.  Open the Applications Settings for the Function App.

Add two new keys named TwilioAccountSid and TwilioAuthToken, setting their values to your Twilio AccountSid and AuthToken respectively. You can find your Twilio credentials in the Twilio Console.

Save the Application Settings ...