Assign value to HiddenField and retrieve in page load using jQuery in ASP.Net

hi

I use hiddenField and put label's value on this hiddenfield:

<asp:HiddenField ID="hfMessageCount" runat="server" />
<asp:HiddenField ID="hfCharacterCount" runat="server" />
<asp:HiddenField ID="hfTextBoxValue" runat="server" />
<asp:HiddenField ID="hfSum" runat="server" />

and below is javacode:

<script type="text/javascript">
        $(function () {
            var i = 0;
            $('[id*=Txtmatn]').keydown(function (e) {
                var ctrlKey = 67, vKey = 86;
                if (e.keyCode != ctrlKey && e.keyCode != vKey) {
                    $('[id*=hfCharacterCount]').val(toPersianNumber($(this).val().length));
                    $('[id*=LbltedaCh]').html($('[id*=hfCharacterCount]').val());
                    $('[id*=hfTextBoxValue]').val($(this).val());
                    if ($(this).val().length % 70 == 0) {
                        i = $(this).val().length / 70;
                        $('[id*=lblsum]').html(i * ($('[Id*=LblTshE]').html()));
                        i = toPersianNumber(i);
                        $('[id*=hfMessageCount]').val(i);
                        $('.MessageCount').html($('[id*=hfMessageCount]').val());
                    }
                    else {
                        i = $(this).val().length / 70;
                        i = toPersianNumber(parseInt(i));
                        $('[id*=hfMessageCount]').val(i);
                        $('.MessageCount').html($('[id*=hfMessageCount]').val());
                    }
                }
            });
            $('[id*=Txtmatn]').keyup(function (e) {
                var ctrlKey = 67, vKey = 86;
                if (e.keyCode != ctrlKey && e.keyCode != vKey) {
                    $('[id*=hfCharacterCount]').val(toPersianNumber($(this).val().length));
                    $('[id*=LbltedaCh]').html($('[id*=hfCharacterCount]').val());
                    $('[id*=hfTextBoxValue]').val($(this).val());
                    if ($(this).val().length % 70 == 0) {
                        i = $(this).val().length / 70;
                        $('[id*=lblsum]').html(i * ($('[Id*=LblTshE]').html()));
                        i = toPersianNumber(i);
                        $('[id*=hfMessageCount]').val(i);
                        $('.MessageCount').html($('[id*=hfMessageCount]').val());
                    }
                    else {
 
                        i = $(this).val().length / 70;
                        i = toPersianNumber(parseInt(i));
                        $('[id*=hfMessageCount]').val(i);
                        $('.MessageCount').html($('[id*=hfMessageCount]').val());
                    }
                }
            });
            $("[id*=Txtmatn]").bind('paste', function (e) {
                setTimeout(function () {
                    $('[id*=hfCharacterCount]').val(toPersianNumber($("[id*=Txtmatn]").val().length));
                    $('[id*=LbltedaCh]').html($('[id*=hfCharacterCount]').val());
                    $('[id*=hfTextBoxValue]').val($("[id*=Txtmatn]").val());
                    var msgCount = $("[id*=Txtmatn]").val().length / 70;
                    $('[id*=lblsum]').html(Math.floor(msgCount) * (Math.floor($('[Id*=LblTshE]').html())));
                    msgCount = toPersianNumber(Math.floor(msgCount));
                    $('[id*=hfMessageCount]').val(msgCount);
                    $('.MessageCount').html($('[id*=hfMessageCount]').val());
                }, 100);
            });
        });
 
        function toPersianNumber(input) {
            var inputstring = input;
            var persian = ["۰", "۱", "۲", "۳", "۴", "۵", "۶", "۷", "۸", "۹"]
            for (var j = 0; j < persian.length; j++) {
                inputstring = inputstring.toString().replace(new RegExp(j, "g"), persian[j]);
            }
            return inputstring;
        }
    </script>

as you see here I used:

$('[id*=hfCharacterCount]').val(toPersianNumber($("[id*=Txtmatn]").val().length));
$('[id*=LbltedaCh]').html($('[id*=hfCharacterCount]').val());
$('[id*=hfTextBoxValue]').val($("[id*=Txtmatn]").val());

now I want put Lblsum value into hfsum

<asp:HiddenField ID="hfLblsum" runat="server" />

how I can do it?

Best regards

neda