asp hidden field not retaining values after postback

Question

Hi.

 

I have a webpage (say W) that is displayed inside an iframe of a main page (say M) .

 

All the below events are in the webpage (W). 

I calculate the gridview total using jquery and store it in a hidden variable. 

I then take the value in code behind from this hidden variable for further calculations on button click. 

 

 This process works neatly when i run the webpage separately.

But when its inside the main page (M), the hidden fields do not retain their values and i get error.

 

 jquery is as follows

 

function TotalTC() {

var txtTotal = 0;

$(".TCTotal").each(function () {

txtTotal += isNaN(parseFloat($(this).html())) ? 0 : parseFloat($(this).html());

});

$('.calTCTotal').html(txtTotal.toFixed(2));

$('#gvToolingCost_hdnTCTotal').val(txtTotal.toFixed(2));

}

 

 

inside buttonclick

 

string hdnAmtTotal = (gvCostWorking.FooterRow.FindControl("hdnAmtTotal") as HiddenField).Value;

this value is blank.

 

Thanks in advance.....