Get checked ASP.Net CheckBoxList values with comma separated using jQuery

Article: Use AJAX Modal Popup Extender inside GridView in ASP.Net

Hellow sir I am tring generate a click event from javascript to bind the Checkboxlist value coming from backend under asp panel here is my front end code

<div>
    <table>
        <tbody>
            <tr>
                <th>Division</th>
                <td>
                    <asp:Panel ID="pnldiv" runat="server" Height="200px" Width="300px" GroupingText=" "
                        ScrollBars="Auto">
                        <asp:CheckBoxList ID="chkdiv" runat="server" class="b">
                        </asp:CheckBoxList>
                    </asp:Panel>
                </td>
            </tr>
        </tbody>
    </table>
</div>

and my binding code like this

chkdiv.DataTextField = "Divname";
chkdiv.DataValueField = "Divname";
chkdiv.DataBind();

it is getting bind to checkboxlist

And i need code that after clicking the checkbox list value it should store in stringvariable with comma seperator in sequence the way i click   in javascript and should visible in my pages that what i had selected without loading the page  and if i unchecked that value that value should disppear from my page without loading pages.

My javascript code is this

$(function () {
    let aaa = '';

    $(".b input").click(function () {

        var props = $(this).prop('checked');
        if (props) {
            var i = $(this).val();
            aaa += i + ','

        }
        else {
            var i = $(this).val();
            var index = aaa.indexOf(i + ',');
            if (index !== -1) {
                aaa = aaa.slice(0, index) + aaa.slice(index + i.length + 1);
            }
        }
        console.log(aaa);
    });

After that i want to click on save button that will save that value in my grid. I will handle this.

Please help.