firing Validation rules under One way binding Mode

Hi,

I am binding a ListBox with Mode = OneTime as i want to bind it first time only , after that if data changes i dont want my listbox to take care of that

 <ListBox x:Name="_statusListBox"
           Margin="18,0"
           Background="Transparent" BorderThickness="0"
           ItemTemplate="{StaticResource StatusListBoxItemTemplate}" 
           ItemsSource="{Binding Summary.ProjectStatusSummary,Mode=OneTime}"
           />

but it works randomly , somethimes it binds data and sometimes it does not

i want to know the reason of this random behavior

Regards,

BHavik

I am migrating my application to MVC3 and getting this error message

Validation parameter names in unobtrusive client validation rules must start with a lowercase letter and consist of only lowercase letters or digits.

How can I ovoid it without going and modifying all my ViewModels

Tank you for your help 

I have several buttons on a page, but have assigned some validators and AJAX validator callout extenders to one button in particular. However, the validator callout extenders seem to be firing even if I press a different button. I thought this was the point of setting a TargetControlID (for the valiator callout extender) and a ControlToValidate for the validator itself! Any suggestions as to what I'm doing wrong?

<asp:TextBox ID="tbNewDuration" runat="server" />   Duration <br />
<asp:RequiredFieldValidator ID="tbNewDurationRFV" ControlToValidate="tbNewDuration" ErrorMessage="Please enter a Duration value." Display="None" runat="server" />
<cc1:ValidatorCalloutExtender ID="tbNewDurationVCE1" runat="server"  TargetControlID="tbNewDurationRFV" />
<asp:RegularExpressionValidator ID="tbNewDurationREV" runat="server" Display="none" ControlToValidate="tbNewDuration" ErrorMessage="Please enter a number of 10 digits" ValidationExpression="^\d{10}$" />
<cc1:ValidatorCalloutExtender ID="tbNewDurationVCE2" runat="server" TargetControlID="tbNewDurationREV" />

Using: WPF (.NET 4) with Entity Framework on a SQLCE database.

In my app, the user can edit existing employees and create new employees. The same UI control is used to add and edit. In the case of editing an Employee, the DataContext for the control is the Employee object of my Entity Framework context. It is updated through binding, and the SaveChanges method is called on my EF to update the database. In the case of adding and Employee, the DataContext is a new Employee object, which will gets added to the EF and then saved. Simple.

I've been trying to hook-up validation to the control. I'm using WPF's ValidationRule objects for each field binding as required. When the field loses focus (as is the default action for a target to source binding), the validation rules are checked, which can incur an error. I can then check for the presence of these errors before allowing the employee to be saved.

But when adding a new Employee, if I go ahead and push the Save button without doing anything else, no validation takes place, becasue the bindings have never attempted to update the source! It just throws an exception as expected.

What can I do? I have ideas which would probably work, but I thought I should post here first in case I am missing something obvious! Is there a standard way to deal with t

I am new in MVC.Using MVC2.MY create view is given below...

<%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<MvcApplication1.Models.ExpenseCategory>" %>
<asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<script src="<%=ResolveUrl("~/Scripts/jquery-1.4.1.min.js")%>" type="text/javascript"></script>
<script language="javascript" type="text/javascript">
        function SaveExpenseCategory() {
            try {

                var requrl = "/ExpenseCategory/Create";
                var formID = "frmAddEC";
                var serdata = $(frmAddEC).serialize();

                $.ajax({