Validation event for asp net client side validation

I wonder if there’s a way to hookup a custom function to asp net client-side validation event, so every time validation is fired by any control I can make some magic on client-side UI

I’m looking for a general approach to intercept page onvalidating event without setting it on every control that causes a postback

Thank you guys


I ended up with this function: (thanks to @Kirk)

$(document).ready(function () {
    $('form').submit(function () {
        if (typeof Page_Validators != 'undefined') {
            var errors = '';
            $.each(Page_Validators, function () {
                if (!this.isvalid) {
                    errors += this.errormessage + 'rn';
            if (errors.length > 0) {


Thank you for visiting the Q&A section on Magenaut. Please note that all the answers may not help you solve the issue immediately. So please treat them as advisements. If you found the post helpful (or not), leave a comment & I’ll get back to you as soon as possible.

Method 1

To do something along the lines of this you can place an OnClientClick event on the submit button or just the general form submission event.

Then you can use the Client Validation Object Model with the validator controls. This actually allows you to verify each of the validation controls you’ve setup. There are a couple of values you can check against from the client relating to the page, see

You reference each control with isvalid property. For example

<asp:Label id="lblZip" runat="server" Text="Zip Code:" />
<asp:TextBox id="txtZip" runat="server" /></asp:TextBox>
<asp:RegularExpressionValidator id="valZip" runat="server"
   ErrorMessage="Invalid Zip Code" 
   ValidationExpression="[0-9]{5}" />

<script language=javascript>
// Call this function to do something
function txtZipOnChange() {
   // Do nothing if client validation is not active
   if (typeof(Page_Validators) == "undefined")  return;
       // Change the color of the label = valZip.isvalid ? "Black" : "Red";

You can also get an array of the validators on the page with the client function Page_Validators. There are a few more functions you can use.

Also you may use the ValidatorValidate(val) client function to force a check of each one indivually as well as ValidatorEnable(val, enable) to enable or disable validators as your logic demands.

Take a look at for a bit more detail.

Hopefully this gets you where you need to go. If not, feel free to ask.

Previous Comment
You can use an onClientClick and attach a JavaScript function.

If you want to use jQuery, you can use ClientIDMode you are able easier to figure out control IDs.

Take a look at

Method 2

//Page_Validators is an array of validation controls in the page. 
if (Page_Validators != undefined && Page_Validators != null) 
    //Looping through the whole validation collection. 
    for(var i=0; i<Page_Validators.length; i++) 
        //if condition to check whether the validation was successfull or not. 
        if (!Page_Validators[i].isvalid) 

//if condition to check whether the page was validated successfully. 

Note the very last code example at the bottom of this page.

All methods was sourced from or, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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