Here Mudassar Ahmed Khan has explained with an example, how to solve the problem i.e. IFormFile always returns NULL when used in Controller while uploading files in ASP.Net Core MVC.

There are two reasons. First the name of the IFormFile parameter and the name of HTML FileUpload element must be exact same and second that the Form element must be specified with the enctype attribute.

Here Mudassar Ahmed Khan has explained why HttpPostedFileBase not working in ASP.Net Core and what is the alternative solution for using the functionality which is used for uploading Files in ASP.Net Core.

Microsoft has permanently removed HttpPostedFileBase class from ASP.Net Core and introduced a new interface IFormFile for uploading Files in ASP.Net Core 2.0 and ASP.Net Core 3.0.

Here Mudassar Ahmed Khan has explained a simple Tutorial with example, how to upload a file in ASP.Net Core MVC.

Multiple files will be selected using HTML FileUpload element and then will be uploaded and sent to Controller.

Inside the Controller, the multiple files will be saved in a Folder (Directory) inside the www Folder in ASP.Net Core MVC.

Here Mudassar Ahmed Khan has explained a short tutorial with example on how to use IWebHostEnvironment interface in ASP.Net Core.

Microsoft has permanently removed Server.MapPath function from .Net Core and introduced a new interfaces IWebHostEnvironment for .Net Core 3.0.