Laziale Laziale - 7 months ago 67
Javascript Question

jquery check if asp checkbox is checked

Hello everyone I have a checkbox I want to check if its checked or no on client side, before postback happens.
Here is the checkbox:

<asp:CheckBox runat="server" CssClass="checkbox" Checked="true" ID="checkboxRules" />

Thanks in advance, Laziale

The problem is that there is a button on the page too which is triggered by js code, and maybe I can add a line there to check if the checkbox is checked once the button is clicked, otherwise display message for unchecked checkbox:

function enterClick() {

var ishown = false;
$(document).ready(function () {
$('#BUTTON').click(function (e) {

//I want to put the checkbox logic here

Thanks again


Since it is a server-side Checkbox, it will send something like <input type="checkbox" class="checkbox" /> as HTML to the client after ASP.NET processes the control.

The id of the checkbox isn't going to be checkboxRules as you have it in the source code. ASP.NET will make a concatenation of the server-side form id + master page id (if using a master page) + checkboxRules so in this case I won't use a selector that depends on element id.

We can make a jQuery selector as narrow as possible to only select inputs with a type of "checkbox" and with a CSS class of "checkbox".

$('input[type=checkbox] .checkbox').attr('checked')

will return the boolean value of the check status of the input. This will find any input on the page that is a checkbox with that CSS class.