how to get the selected index of check box from checkboxlist control using jquery?

Greetings, how to get the selectedindex of check box from checkboxlist control using jquery?

Update:

This code is giving me selected index equal 0 please advive

<asp:CheckBoxList ID="chkListGroups" runat="server" 
                    styl开发者_StackOverflow中文版e="position:absolute; top: 1115px; left: 745px; bottom: 371px;" 
                    DataSourceID="SqlDSGroups" DataValueField="Groups" 
                    onclick="test()">
                </asp:CheckBoxList>


....................
java script function
.....................
  function test(){
  $('#<%=chkListGroups.ClientID %>').click(function() {
                var selectedIndex = $('#<%=chkListGroups.ClientID %>').index($(this));


                alert(selectedIndex);


            });
        }

Use a selector for the collection, then use index with the element that you are interested in, here the one that is checked.

var checkboxes = $('input:checkbox');
var selectedIndex = checkboxes.index(checkboxes.find(':checked'));

To get the index of a clicked checkbox use:

$('input:checkbox').click( function() {
    var selectedIndex = $('input:checkbox').index( $(this) );
    ... now do something with it...
});

EDIT: Based on your code sample:

var checkboxes = $('#<%=chkListGroups.ClientID %>').find('input:checkbox');
checkboxes.click(function() { 
    var selectedIndex = checkboxes.index($(this)); 
    alert(selectedIndex); 

});  

get value: $("input:checked").val();
get id: $("input:checked").attr('id');

//or this:
var counter=0;
$('input:checkbox').each(function(){
   if($(this).is(":checked"))
   {
     var Index = counter;
   }
   else{
     counter++;
   }

   //So Index is what you want.
});

I haven't tested this, but it's something like this code. I hope it helps you

like so if you need the index of the last selected checkbox

var query = (from o in CheckBoxList1.Items.OfType<ListItem>()  
                     where o.Selected  
                     select o).Take(1).Reverse().ToList();