Question

I have an ASP.NET MVC 3 application which has a post action called Create:

[HttpPost]
public virtual ActionResult Create(Issues issues)
{
    if (ModelState.IsValid)
    {
        context.Issues.Add(issues);
        context.SaveChanges();
        return RedirectToAction("Index");
    }
    return View(issues);
}

If I double click on the submit button by mistake, it’ll Create 2x issues. Is there a way of preventing this, without the use of javascript and disabling the button, I thought the whole use of using a RedirectToAction was to prevent this, by using the Post/Redirect/Get design pattern?

Answer 1

The pattern you mentioned (Post/Redirect/Get design pattern) prevents page refreshes from double posting because the last action is a GET, not the POST.

If you want to prevent double clicks from double posting, you could:

1. Disable the button after click
2. Maintain a unique index on 'Issues' and look for duplicates
3. Maintain something in session that gives you an indication of a double post

And there maybe a few more ways… I think disabling the button is probably the easiest because you’re redirecting to another page anyway.