How can I handle errors in an ASP.NET Core API?

How can I handle errors in an ASP.NET Core API?

You can handle errors in an ASP.NET Core API by using middleware, exception filters, or the built-in error handling features.

What is the best way to implement global error handling?

The best way is to create a custom middleware that catches exceptions and returns a standardized error response.

Can you show me an example of custom middleware for error handling?

Sure! Here's a simple example:

public class ErrorHandlingMiddleware {
    private readonly RequestDelegate _next;

    public ErrorHandlingMiddleware(RequestDelegate next) {
        _next = next;
    }

    public async Task InvokeAsync(HttpContext context) {
        try {
            await _next(context);
        } catch (Exception ex) {
            await HandleExceptionAsync(context, ex);
        }
    }

    private Task HandleExceptionAsync(HttpContext context, Exception ex) {
        context.Response.ContentType = "application/json";
        context.Response.StatusCode = (int)HttpStatusCode.InternalServerError;
        return context.Response.WriteAsync(new ErrorResponse {
            Message = "An error occurred while processing your request."
        }.ToString());
    }
}

How do I register this middleware in the Startup class?

You can register it in the Configure method of your Startup class like this:

public void Configure(IApplicationBuilder app, IWebHostEnvironment env) {
    app.UseMiddleware<ErrorHandlingMiddleware>();
    // other middleware registrations
}