Question

From my page’s code-behind I want to access the value of this hidden field. The value is set properly. I confirmed by checking its value.

<div class="hiddenValues">
    <input id="HiddenReportId" type="hidden" />
</div> 

From my code behind, I’m using the following to access the above input

string id = Request.Form["HiddenReportId"];

When I run the application this line throws a null exception. Any suggestions ? Thanks!

Answer 1

The input needs to be inside of the form tag (which it may be, can’t tell from the code snippet). Also, it needs to have a name attribute:

<div class="hiddenValues">
  <input id="HiddenReportId" name="HiddenReportId" type="hidden" />
</div>

Its id attribute may be redundant and isn’t necessary if you’re not using it. But form elements are identified by their name attributes in a POST.

(It feels a bit unintuitive from an ASP.NET perspective to the uninitiated, I know. ASP.NET convention is to identify everything by an ID, but web browsers use name when crafting a POST. And the web browser knows nothing of the server-side technology being used, it follows HTTP standards instead.)