Question

Assuming that I’m talking about an ASP.NET MVC 3 application, the scenario is something like

1. I browse to the URL http://localhost:60088/Example?param1=test123 that returns a view
2. Next I click a button that triggers an Ajax call to the URL http://localhost:60088/Example/DoSomethign that returns a JSON string

So, my dilemma is that in the DoSomething controller action I need to get the param1 parameter that was passed in the first step.

My first take is to do something like this:

public ActionResult DoSomething()
{
    ...

    Uri baseUrl = this.Request.UrlReferrer;
    // Somehow extract the parameter from baseUrl

    ...
}

But I’m not sure if that’s a good idea at all…

Questions:

1. Is safe to assume that this.Request.UrlReferrer will always have the URL that was called in a non-callback way (even if I made several more callbaks after the _DoSomething_ first callback)?

2. Is there a better way to accomplish waht I’m trying to do?

Answer 1

No; you cannot assume that the referrer will always exist.

Instead, you should include the original URL as a parameter in the AJAX request.