How to Use AutoMapper With .NET Core 3.1 Web API

Start by installing the AutoMapper extension from the package manager in your project. In PowerShell, or with the package manager console in Visual Studio, type:

Install-Package AutoMapper.Extensions.Microsoft.DependencyInjection

Register a service in ConfigureServices in the startup.cs file:

// startup.cs

using AutoMapper; 
public void ConfigureServices(IServiceCollection services)
{ 
    services.AddAutoMapper(typeof(Startup)); 
}

Add an AutoMapping.cs file with the following content:

// AutoMapping.cs

public class AutoMapping : Profile
{
    public AutoMapping()
    {
        CreateMap<CreateProductRequest, Product>();
    }
}

Inject a mapper into your controller:

private readonly IMapper mapper;
public ProductController(IMapper mapper)
{
    this.mapper = mapper;
}

public async Task<ActionResult> CreateProduct(CreateProductRequest request)
{
    var product = mapper.Map<Product>(request);
...

Voila! Now, whenever you add new properties to your object the mapping should be handled automatically.