How to Add Swagger in .NET 9 and .NET 10?

Introduction

Swagger is an essential tool for documenting and testing APIs. In .NET 9 or .NET 10, integrating Swagger with Minimal APIs or traditional controllers is straightforward. This article will guide you through the process step by step.

Prerequisites

• .NET 9 or 10 SDK installed

• A .NET 9 or 10 Web API project

• Visual Studio or any preferred code editor

Create a New API Project

Click right on the project, go to Manag Nuget Package.. as below image and install it.

Open Program.cs and update the code below.

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.Services.AddControllers();

builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

var app = builder.Build();

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseHttpsRedirection();

app.UseAuthorization();

app.MapControllers();

app.Run();

Open launchSettings.json  from the Properties folder and add the below code.

{
  "$schema": "https://json.schemastore.org/launchsettings.json",
  "profiles": {
    "http": {
      "commandName": "Project",
      "dotnetRunMessages": true,
      "launchBrowser": false,
      "applicationUrl": "http://localhost:5250",
      "environmentVariables": {
        "ASPNETCORE_ENVIRONMENT": "Development"
      }
    },
    "https": {
        "commandName": "Project",
        "dotnetRunMessages": true,
        "launchBrowser": true,
        "launchUrl": "swagger",
        "applicationUrl": "https://localhost:7026;http://localhost:5250",
        "environmentVariables": {
            "ASPNETCORE_ENVIRONMENT": "Development"
        }
    }
  }
}

Remember, please run the project with https. See the output below.