How to configure Azure Function’s startup

Time needed: 10 minutes.

How to add a StartUp.cs file for your Azure Functions project?

1. Add a new C# class file to your project.

   This file can be named pretty much anything, but I reckon a good convention is to place it at the root of your project and maybe even call it StartUp.cs
   
2. Select the file and open it up

   It’ll look somewhat like this:
   

3. Add the following using -statements

   
   using Microsoft.Azure.WebJobs;
using Microsoft.Azure.WebJobs.Hosting;

   In a matter of seconds, these will give you access to the attributes and interfaces that you will need!

4. Add the following attribute to your namespace

   
   [assembly: WebJobsStartup(typeof(StartUp))]
   
   This defines your class to be run at the startup of your Azure Functions app!
5. Add the following interface to your StartUp class

   
   StartUp : IWebJobsStartup
   
   That’ll instruct the runtime to run the right thing, and gives you instructions on what to implement, such as…

6. Implement Configure ()

   Somewhat like below:
   
   public void Configure(IWebJobsBuilder builder)
{
}

7. Finally, add a reference to your own project

   In my case, it’s like below:
   
   using StartUpExample;
   
   Below is an example of all of the things you need to add:
   
   
8. Now you can configure your services just like you would in a .NET Core Web API project!

   … well, almost. Adding services happen by accessing the IServiceCollection under builder – like so, for adding an Entity Framework Core database context with some configuration options presented:
   
   builder.Services.AddDbContext(options1 =>
{
options1.UseLazyLoadingProxies(false);
options1.UseSqlServer(
config["ConnectionStrings:DefaultConnection"],
builder =>
{
builder.EnableRetryOnFailure(5, TimeSpan.FromSeconds(10), null);
builder.CommandTimeout(10);
}
);
});