In a follow up to my previous question, I want to get the value of the hidden input field from the child page codebehind.
I tried HtmlInputHidden hdnID = (H
HtmlInputHidden hdnID = (H
I don't think you need to prefix the hidden field's ID with ctl00_, just use the normal ID:
ctl00_
(HtmlInputHidden)Page.Master.FindControl("hdnField");