Page.Request.QueryString has a value although none was passed to the page

Question

We have the following code that is returning a value of "3" although no value is passed as a query string. Is there some way that the "id" is getting stuck in the server memory (since it is not user specific) or is "id" a special value. Any ideas?

if (Page.Request.QueryString["id"] != null)
{
Page.Trace.Write("Query String Key Found");
ListItemID = HttpContext.Current.Request.QueryString["id"];
}

This is in a SharePoint 2007 webpart.

Answer 1

If the webpart is on page that was navigated to by clicking a list item from the previous page; you'd be seeing the id of that list item.

Answer 2

There probably is a post (or GET) with parameters somewhere, that's hidden from you. Querystrings are the GET variables that are past along and there is no "stuck" or "server memory".

Use a tool like HTTPAnalyzer or Fiddler to analyze the HTTP traffic. That will show you who's making what requests. Although it's probably the ID of the control you're clicking on since you're in Sharepoint.

Answer 3

Clear the browser cache.

Answer 4

Usually, when a webpart gets added, all parameters that it has available for input get assigned a default value, for instance, add a dataformwebpart to an ampty page and bind it to a list. Then open the source of the page. You see a bunch of parameterbindings there, which in turn can be bound to querystrings. Could you if your webpart got assigned a default value for ListItemId?

Or are you actually debugging and stepping into this particular piece of code and the id querystring variable actually contains 3? If so, I agree with one of the other answers, use Fiddler to check how many http calls are made when you open the page.