A Practical Approach Through a Console Application

Custom error pages in ASP.NET MVC Core

app.Use(async (ctx, next) =>
{
    await next();

    if(ctx.Response.StatusCode == 404 && !ctx.Response.HasStarted)
    {
        //Re-execute the request so the user gets the error page
        string originalPath = ctx.Request.Path.Value;
        ctx.Items["originalPath"] = originalPath;
        ctx.Request.Path = "/error/404";
        await next();
    }
});

The Unknown Error Code 

Handling errors in an ASP.NET Core Web API 

Error Handling in Large .NET Projects - Best Practices  

Error Handling in ASP.NET Core  

This post is about the concept of middleware in Core. We have named the post Error Logging Middleware in ASP.NET Core, because we want to use error logging as an example of utilizing middleware

Error Handling  Asp.net