TL;DR Transient objects are always different; a new instance is provided to every controller and every service. Scoped objects are the same within a request, but different across different requests. Singleton objects are the same for every object and every request. For more clarification, this example from .NET documentation shows the difference: To demonstrate the … Read more
At the top of your Razor View just add Notice the @ char before the using statement. Or inside a block like below: Side note: it’s a little bit weird to use a SqlConnection into a Razor View.
For the Dependency Injection framework to resolve IRepository, it must first be registered with the container. For example, in ConfigureServices, add the following: AddScoped is just one example of a service lifetime: For web applications, a scoped lifetime indicates that services are created once per client request (connection). See the docs for more information on Dependency Injection in ASP.NET Core.
To break down the error message: Unable to resolve service for type ‘WebApplication1.Data.BloggerRepository’ while attempting to activate ‘WebApplication1.Controllers.BlogController’. That is saying that your application is trying to create an instance of BlogController but it doesn’t know how to create an instance of BloggerRepository to pass into the constructor. Now look at your startup: That is saying whenever a IBloggerRepository is required, create a BloggerRepository and … Read more
This may have to do with ASP NET Core 2.2 as you figured. There’s an issue registered on GitHub https://github.com/aspnet/AspNetCore/issues/4398 And the work-around is as follows – add the following bit of code in your startup.cs class (I’ve kept this first in Configure method) Do keep track of the GitHub issue.
I am using Microsoft Visual Studio 2019 Community preview, version 16.4.0 Preview 1.0. I just update to Windows 10 Pro Version 1903 OS build 18362.418 . With ASP.NET Core 3 web-app project (Blazor Server), When I press F5, I catch error I can go to https://localhost:44333/ manually, but it is inconvenient. When I stop debug, I also turn … Read more