How to invoke a function but don't wait to finish - ASP.NET

Question

I got one page where i do some file manipulation, and when file is done, i need to upload to amazon s3. Sometimes file can be large, so user on submit need to wait too much. How can i make something like

1. File manipulation
2. When is done, i send file name parameters to some function
3. I don't need to wait for that function, i want to use Response.Redirect before uploading is done.

Answer 1

Easiest way to do this:

ThreadPool.QueueUserWorkItem(YourUploadMethod);

There is some comment below arguing with this, so I wrote this:

    protected void Page_Load(object sender, EventArgs e)
    {
        ThreadPool.QueueUserWorkItem(YourUploadMethod);

        Response.Redirect("http://google.com");
    }

    public void YourUploadMethod(object state)
    {
        Thread.Sleep(7000);
    }// breakpoint: I was redirected to google and then debugger stopped me here