多个控件上的asp.net CustomValidator

Question

I am working with a page that has a series of checkboxes that at least one box must be checked.

The validator fires when I click the submit button and if no checkboxes are checked indicates the validation has failed. However If I check one of the checkboxes the validation message does not go away until I click the submit button again.

If I was using this on a control in which I had specified the ControlToValidate and I fixed the validation issue the error message goes away immediately.

However in this case I am not setting the ControlToValidate due to the need to validate several independent controls.

So my question is can I cause a re-validation of the custom validator? For instance I would like to add on each checkbox a onclick="revalidate()" that would then force the validation to happen again.

Here is some sample code that I wrote to demonstrate the scenario.

<script type="text/javascript">
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script>
    function IsOneCheckboxChecked(sender, args) {
        if (!$('[id$=checkBox1]').attr('checked') &&
    !$('[id$=checkBox2]').attr('checked')) {
            args.IsValid = false;
        }
        else {
            args.IsValid = true;
        }
    }
</script>



<asp:CheckBox ID="checkBox1" runat="server" />
<br />
<asp:CheckBox ID="checkBox2" runat="server" />
<br />
<asp:CustomValidator ID="customValidatorMustBeOnCheckboxChecked" 
    runat="server" ClientValidationFunction="IsOneCheckboxChecked"
    ErrorMessage="You must select at least one checkbox option" 
    OnServerValidate="customValidatorMustBeOnCheckboxChecked_ServerValidate" />
<br />
<br />
<asp:Button ID="buttonSubmit" runat="server" Text="Submit" />

Answer 1

Yes there is a way of revalidating before the commit is clicked. ASP.NET builds an 'onBlur' event that binds to the control you are validating in javascript, which runs the code you define in client validation function. This is running but of course you are clicking a checkbox then submit again - onBlur only kicks in when you click elsewhere before clearing the message. So I would call your client validation function on a mouseleave or mouseover event before the user gets to the submit button. This would clear the message and keep your args.IsValid set correctly, so by the time the user clicks submit the error message is gone and the form validates.

for example:

$(".submitButtonDiv").mouseenter(function () {
    IsOneCheckboxChecked();
});

Answer 2

Well I was able to solve the issue by finding the span that the control validator creates and in my revalidate method hide or expose the error message. However I would like to think something better exists?

I created a blog entry on this at:

http://coding.infoconex.com/post/ASPNET-CustomValidator-that-validates-multiple-controls-using-both-Server-Side-and-Client-Side-scripting.aspx

 function Revalidate() {
        if (!$('[id$=checkBox1]').attr('checked')
        && !$('[id$=checkBox2]').attr('checked')) {
            var control = $('[id$=customValidatorMustBeOnCheckboxChecked]');
           control.css('display', 'inline');
        }
        else {
            var control = $('[id$=customValidatorMustBeOnCheckboxChecked]');
            control.css('display', 'none');
        }
    }

<asp:CheckBox ID="checkBox1" runat="server" onclick="Revalidate()" />
<br />
<asp:CheckBox ID="checkBox2" runat="server" onclick="Revalidate()" />