Introduction
Azure Functions is a serverless compute service that lets you run code on-demand without managing infrastructure. In this tutorial, you'll build a simple HTTP-triggered function from scratch.
Prerequisites
- Visual Studio Code or Visual Studio 2022
- .NET 8 SDK
- Azure Functions Core Tools v4
- An Azure account (free tier works)
Step 1: Create the Project
Open your terminal and run:
func init MyFirstFunction --dotnet --worker-runtime dotnet-isolated
cd MyFirstFunction
func new --name HelloWorld --template "HTTP trigger" --authlevel anonymous
This creates a new Azure Functions project with an HTTP-triggered function.
Step 2: Understand the Code
Open HelloWorld.cs and review the generated code. The function is decorated with [Function("HelloWorld")] and responds to HTTP GET and POST requests.
[Function("HelloWorld")]
public IActionResult Run(
[HttpTrigger(AuthorizationLevel.Anonymous, "get", "post")] HttpRequest req)
{
_logger.LogInformation("C# HTTP trigger function processed a request.");
return new OkObjectResult("Welcome to Azure Functions!");
}
Step 3: Run Locally
Start the local development server:
func start
Navigate to http://localhost:7071/api/HelloWorld in your browser to test.
Step 4: Add Business Logic
Enhance the function to accept a name parameter and return a personalized greeting. Parse query parameters and request body to build a dynamic response.
Step 5: Deploy to Azure
Use the Azure CLI or VS Code extension to deploy your function to a Function App in Azure. Configure application settings and monitor the deployment.
az functionapp create --resource-group myRG --consumption-plan-location eastus --runtime dotnet-isolated --functions-version 4 --name myFuncApp --storage-account mystorageaccount
func azure functionapp publish myFuncApp
