Today , There are Asp.Net (System.Web.HttpContext) and Asp.Net Core (Microsoft.AspNetCore.Http.HttpContext) in .net Framework , and there are a few packages use .net Framwork with System.Web.HttpContext and .net Core (.net standard) with Microsoft.AspNetCore.Http.HttpContext for sharing source , so when I use Asp.Net Core on .Net Framework , I just can not use that package because that package fouce me to use System.Web.HttpContext , but there is an available assembly in that package, How do I choose that ?