Question

I want to get a codebehind value in my javascript function. My scenario is, Lets say I have two Usercontrols A and B.
I am setting a global value from UserControl A. When I come to UserControl B’s page load, I am accessing that value and putting it into a hidden field.
I have a button on UserControl B which calls a javascript function on client click.
On that function I am trying to catch the hiddenfields current value. But I always get 0 from the hidden field value. What I am doing wrong? Can someone help me?

Below is the code:

<%@ Control Language="vb" AutoEventWireup="false" CodeBehind="DetailsForm.ascx.vb" Inherits="TD_Web_App.DetailsForm" %>
<script type="text/javascript">
function GetNextRecord() {
    debugger;
    var currentVal = $get("DetailsFormPanel_DetailsForm1_HFDetails").value; 
//clientID of my hidden field
}
</script>
<asp:UpdatePanel ID="DetailInfoUpdatePanel" runat="server" UpdateMode="Conditional" > 

  <ContentTemplate>
<table id="TDPropsGrid" runat="server" width="250px" ></table>
    <asp:Button ID="Cmd_Next" runat="server" Text="Next" Width="100px" SkinID="ButtonSkin" UseSubmitBehavior="false" OnClientClick="GetNextRecord()"/>
<asp:LinkButton ID="LinkButtonDetails" runat="server" style="display:none;">
LinkButton 
</asp:LinkButton>
</ContentTemplate>
</asp:UpdatePanel>

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

On code behind:

 Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    showData() 'some function
    HFDetails.Value = CurrentRecordCounter  ' global value coming from other usercontrol 
End Sub

'Private Sub Page_PreRender(sender As Object, e As System.EventArgs) Handles Me.PreRender
'    HFDetails.Value = CurrentRecordCounter
'End Sub

I have tried putting

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

inside the update panel, nothing changed.

But at GetNextRecord() the currentVal is always “0”. why?

Answer 1

Try:

var currentVal = $('#<%=HFDetails.ClientID %>').val();