tab control item contain individual pages - asp.net

Question

My tab control items contain three different pages.Clicking on tabitem ,they are visible,but when want to perform javascript event on page item then problem arise.javascript well works for only first tab control item,rest of them are not work.Show me the bellow error.
Microsoft JScript runtime error: 'this.GetStateInput().value' is null or not an objec
tabcontrol
**tab item1 contain page1
tab item2 contain page2
tab item3 contain page3**
i write javascript on page1 control,it's work well but rest of pages javascript show the above error message. i work on devexpress control
<%# Control Language="C#" AutoEventWireup="true" CodeBehind="UCCharge.ascx.cs" Inherits="WebCore.UserControls.ChargeSettings.UCCharge" %>
<%# Register assembly="DevExpress.Web.v9.1, Version=9.1.2.0, Culture=neutral, PublicKeyToken=5377c8e3b72b4073" namespace="DevExpress.Web.ASPxTabControl" tagprefix="dxtc" %>
<%# Register assembly="DevExpress.Web.v9.1, Version=9.1.2.0, Culture=neutral, PublicKeyToken=5377c8e3b72b4073" namespace="DevExpress.Web.ASPxClasses" tagprefix="dxw" %>
<%# Register src="UCConfig_Charge_Company_Wise.ascx" tagname="UCConfig_Charge_Company_Wise" tagprefix="uc1" %>
<%# Register src="UCConfig_Charge_Depository_Company_Wise.ascx" tagname="UCConfig_Charge_Depository_Company_Wise" tagprefix="uc2" %>
<%# Register src="UCconfig_charge_operation_mode.ascx" tagname="UCconfig_charge_operation_mode" tagprefix="uc3" %>
<%# Register src="../InvestorAccount/UCconfig_Investor_Account_Wise_Charge.ascx" tagname="UCConfig_Investor_Account_Wise_Charge" tagprefix="uc4" %>
<table>
<tr>
<td>
<dxtc:ASPxPageControl Width="500px" ID="ASPxPageControl1" runat="server" ActiveTabIndex="0"
EnableCallbackCompression="True" EnableHierarchyRecreation="True"
AutoPostBack="True">
<TabPages>
<dxtc:TabPage Text="Charge Company">
<ContentCollection>
<dxw:ContentControl ID="ContentControl1" runat="server">
<uc1:UCConfig_Charge_Company_Wise ID="UCConfig_Charge_Company_Wise" runat="server" />
</dxw:ContentControl>
</ContentCollection>
</dxtc:TabPage>
<dxtc:TabPage Text="Charge Depository Company">
<ContentCollection>
<dxw:ContentControl ID="ContentControl3" runat="server">
<uc2:UCConfig_Charge_Depository_Company_Wise ID="UCConfig_Charge_Depository_Company_Wise"
runat="server" />
</dxw:ContentControl>
</ContentCollection>
</dxtc:TabPage>
<dxtc:TabPage Text="Investor Charge ">
<ContentCollection>
<dxw:ContentControl ID="ContentControl5" runat="server">
<uc4:UCConfig_Investor_Account_Wise_Charge ID="UCConfig_Investor_Account_Wise_Charge"
runat="server" />
</dxw:ContentControl>
</ContentCollection>
</dxtc:TabPage>
<dxtc:TabPage Text="Charge Operation Mode ">
<ContentCollection>
<dxw:ContentControl ID="ContentControl4" runat="server">
<uc3:UCconfig_charge_operation_mode ID="UCconfig_charge_operation_mode"
runat="server" />
</dxw:ContentControl>
</ContentCollection>
</dxtc:TabPage>
</TabPages>
</dxtc:ASPxPageControl>
</td>
</tr>
</table>

Answer 1

I read on a Support issue of a user getting this error, in his case it was because he was using value (myTextBox.value) when getting the value of a DX Control instead of the GetValue() (myTextBox.GetValue()) client method DX provides. Could this be the same thing happening in your code as well?