Step-by-Step Guide to Creating an Azure Function in Visual Studio 2022

Azure Functions are an easy and scalable way to run code without managing servers. In this guide, we'll walk through creating a simple Azure Function called "Add" that takes in two integers, adds them together, and returns the sum. We'll be using Visual Studio 2022 for this example.

Step 1: Install Necessary Tools

Ensure you have the following installed:

• Visual Studio 2022 with the Azure Development workload.
• Azure Functions Core Tools (comes with the workload above).
• Azure SDK (if you want to publish your function to Azure later).

Step 2: Create a New Azure Function Project

1. Open Visual Studio 2022.
2. Go to File > New > Project.
3. Search for Azure Functions and select Azure Functions from the template list.
4. Name your project and click Create.

Step 3: Select the Function Type

1. In the Create a new Azure Functions application dialog: Choose .NET 6.0 (LTS) as the runtime stack. Select HTTP trigger as the function template. Set the Authentication Level to Anonymous.

Step 4: Modify the Function Code

In the Function1.cs file, update the function to accept two integers as query parameters and return their sum. Replace the existing code with the following:

using System.IO;

using Microsoft.AspNetCore.Mvc;

using Microsoft.Azure.WebJobs;

using Microsoft.Azure.WebJobs.Extensions.Http;

using Microsoft.AspNetCore.Http;

using Microsoft.Extensions.Logging;

using Newtonsoft.Json;

public static class AddFunction

{

    [FunctionName("Add")]

    public static IActionResult Run(

        [HttpTrigger(AuthorizationLevel.Anonymous, "get", "post", Route = null)] HttpRequest req,

        ILogger log)

    {

        log.LogInformation("Processing request to add two numbers.");

        string num1String = req.Query["num1"];

        string num2String = req.Query["num2"];

        if (int.TryParse(num1String, out int num1) && int.TryParse(num2String, out int num2))

        {

            int result = num1 + num2;

            return new OkObjectResult($"The sum of {num1} and {num2} is {result}");

        }

        else

        {

            return new BadRequestObjectResult("Please provide valid integers for num1 and num2.");

        }

    }

}        

Step 5: Run the Azure Function Locally

1. Press F5 to run the function locally. This will launch the Azure Functions runtime.
2. The terminal will show the URL where the function is hosted locally. It will look something like https://localhost:7071/api/Add.

Step 6: Test the Function

Open a browser and navigate to:

https://localhost:7071/api/Add?num1=5&num2=3        

You should see a response like:

The sum of 5 and 3 is 8        

Step 7: Deploy to Azure (Optional)

Once you're ready to deploy, follow these steps:

1. Right-click your project in Solution Explorer.
2. Select Publish > Azure > Azure Function App (Windows).
3. Follow the wizard to select or create a Function App in Azure.

Conclusion

You've successfully created an Azure Function in Visual Studio 2022 that adds two numbers! This simple example demonstrates how easy it is to get started with serverless computing using Azure Functions.