The below code snippet explains how to get checked or selected items from ASP.Net CheckBoxList client side using jQuery
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
    <title></title>
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
    <script type = "text/javascript">
        $("#demo").live("click", function () {
            var selectedItems = "";
            $("[id*=chkFruits] input:checked").each(function () {
                if (selectedItems == "") {
                    selectedItems = "Selected Items:\r\n\r\n";
                }
                selectedItems += $(this).next().html() + "\r\n";
            });
            if (selectedItems != "") {
                alert(selectedItems);
            } else {
                alert("No item has been selected.");
            }
        });
    </script>
</head>
<body>
    <form id="form1" runat="server">
    <asp:CheckBoxList ID="chkFruits" runat="server">
        <asp:ListItem Text="Mango" Value="1"></asp:ListItem>
        <asp:ListItem Text="Apple" Value="2"></asp:ListItem>
        <asp:ListItem Text="Banana" Value="3"></asp:ListItem>
        <asp:ListItem Text="Pineapple" Value="4"></asp:ListItem>
        <asp:ListItem Text="Orange" Value="5"></asp:ListItem>
    </asp:CheckBoxList>
    <input type = "button" id = "demo" value = "Demo" />
    </form>
</body>
</html>
 
 
Explanation:
In the above code snippet an HTML Button demo has been assigned jQuery click event handler. When the button is clicked, I fetch all the checked checkboxes from the ASP.Net CheckBoxList chkFruits using the selector [id*=chkFruits] input:checked. Then I loop through the checked Items and then display the selected items in JavaScript alert box.
 
Demo