how to save IFormFile to disk
Edit
In asp .net mvc you could save System.Web.HttpPostedFile to a disk using HttpPostedFile's method SaveAs("filename.ext"). Check the code below on how to save IFormFile to disk.
Solution
IFormFileCollection files = HttpContext.Request.Form.Files;
IFormFile file = files[0];
using (Stream fileStream = new FileStream(Path.Combine(sPath modifiedFileName), FileMode.Create))
{
file.CopyTo(fileStream);
}