So far, we have only created functions in the Azure portal, but this isn't ideal. First, the portal doesn't provide proper tools for writing complex code. Second, your code isn't included in source control. Third, your code isn't covered in unit tests and automated builds. Finally, you can never deploy your functions to other environments through continuous deployment. So, while it's nice for simple use cases, try to avoid creating functions in the portal and use Visual Studio instead.
Now, we are going to create our functions using Visual Studio 2017. To follow along with these examples, you need to have the Visual Studio Azure development workload installed, which you can select when you install or modify Visual Studio. To check whether you have it or not, open Visual Studio, create a new project, and look...