Guide to File Upload in ASP.NET MVC: Step-by-Step Tutorial

 To perform file upload in ASP.NET MVC, you can follow these steps:

1. Create a View: Start by creating a view that contains a form for file upload. This view will typically have an HTML form with an input field of type "file" to select the file.

html
@using (Html.BeginForm("Upload", "ControllerName", FormMethod.Post, new { enctype = "multipart/form-data" }))
{
    <input type="file" name="file" />
    <input type="submit" value="Upload" />
}

2. Create an Action Method: In your controller, create an action method that handles the file upload. This method should have a parameter of type HttpPostedFileBase or IFormFile to receive the uploaded file.

csharp
[HttpPost]
public ActionResult Upload(HttpPostedFileBase file)
{
    if (file != null && file.ContentLength > 0)
    {
        // Process the file here
        // You can save it to the server or perform any other operations

        // Example: Save file to the server
        var fileName = Path.GetFileName(file.FileName);
        var path = Path.Combine(Server.MapPath("~/Uploads"), fileName);
        file.SaveAs(path);

        // Optionally, you can return a success message or redirect to another view
        return RedirectToAction("Success");
    }

    // If no file was selected or the file is empty, handle the error
    ModelState.AddModelError("", "Please select a file.");
    return View();
}

3. Configure Route: Ensure that your route configuration in RouteConfig.cs or Startup.cs allows the correct mapping for the action method in your controller.

4. Set Folder Permissions: Make sure the folder where you intend to save the uploaded files has proper write permissions for the user account under which your ASP.NET application runs.

That's it! You have now implemented file upload in ASP.NET MVC. The uploaded file will be available in the file parameter of the action method, and you can process it as needed.