ASP.NET Partial Postback form value problem

In my page_load I am creating a

HiddenField newField= new HiddenField();

and then I am assigning newField.ID = "someid" and Value="0" to it. on a partial postback (triggered by an UpdatePanel) i am then checking

Request.Form["someid"]

in the panel_Load event during the postback. but the request returns null as someid wasn't posted back. (not contained in the Req开发者_开发技巧uest.Form collection) Why could this be?

Thanks

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ASP.NET mangles the ID when rendered to the client by default. To access it from the Form collection, try this:

Request.Form[newField.ClientID]