<asp:CheckBox ID="ckbTable" runat="server" Checked="false" /><table id="table" style="display:none" border="0" cellspacing="0" cellpadding="0" ><tr><td>123</td></tr></table>

$(function(){$("#ckbTable").click(function () {                if (this.checked) {                    $("#table").css("display", "block");                }                else {                    $("#table").css("display", "none");                }            });});