.NET Core Web API - Exception Handling Middleware and Error Controller

Startup.cs

// ErrorController.cs
[ApiController]
public class ErrorController : ControllerBase
{
    // URL for this API - /api/error
    [Route("/error")]
    public IActionResult Error() => Problem();
}

// Startup.cs
public class Startup
{
    public void ConfigureServices(IServiceCollection services)
    {
        services.AddControllers();
    }

    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
        // Apply ExceptionHandler middleware 
        app.UseExceptionHandler("/api/error");
        
        // Other code is not shown here
    }
}