Find Check box id inside GridView or Table Control with Jquery

function FindControlInsideGridView() {

            var _Table1 = document.getElementById('<%= Table1.ClientID %>');

            $(_Table1).find("tr").each(function(index) {

                var mytd = $(_Table1).find("tr").eq(index).find("td").eq(0);

                if (mytd[0].childNodes[0].checked) {

            //Do some thing

                }

            });

        }