ASP.NET Core 2 - How to call and manipulate a Database class from a controller - asp.net-mvc

Question

I am using ASP.NET Core 2 and I have a controller that runs Tasks.
For example, the one below does a simple file upload, I have others that run other Tasks or Actions and I want to be able to log the events or tasks into my database.
So I need to create a class to run INSERTs or UPDATEs on a database.
How do I create a class that does my database manipulation either using DbContext or call a stored procedure using a class (and not a controller)?
Here is a sample of one of my controller's code:
public async Task<IActionResult> Uploads(string fullName, IFormFile pic)
{
try {
string user = null;
try
{
user = User.Identity.Name.ToString();
}
catch (Exception err)
{
user = "anonymous";
}
if (user == null)
{
user = "";
}
string path = he.WebRootPath + "/uploads/" + user ;
if (!Directory.Exists(path))
{
Directory.CreateDirectory(path);
}
DateTime date = DateTime.Now ;
var dates = date.ToLongDateString();
var ext = Path.GetExtension(path).ToLowerInvariant();
var fileName = Path.Combine(he.WebRootPath + "/uploads/" + "/" + user, Path.GetFileName(pic.FileName));
var f = Path.Combine(he.WebRootPath + "/uploads/" + "/" + user, dates+Path.GetFileName(pic.FileName));
int i = 0;
ViewData["fname"] = fullName;
if (pic != null || pic.Length == 0)
{
using (var stream = new FileStream(fileName, FileMode.Create))
{
await pic.CopyToAsync(stream);
}
ViewData["fileLocation"] = "/uploads/" + user + "/" + Path.GetFileName(pic.FileName);
// }
}

Answer 1

You can use dependency injection to inject your DbContext into your controller:
public class MyController : Controller
{
private readonly DbContext _db;
public MyController(DbContext db)
{
_db = db;
}
public async Task<IActionResult> Uploads(string fullName, IFormFile pic)
{
_db.ExecuteSql("INSERT ...");
}
}
Once you have your Db context, you can do what you need with it.