js动态添加表格

<script type="text/javascript">
        //全局变量
        var i=0;
        //添加行
        function addMyRow(){
            var mytable = document.getElementById("mybody");
            var mytr = mytable.insertRow();
            mytr.setAttribute("id","tr"+i);
            var mytd_1=mytr.insertCell();
            var mytd_2=mytr.insertCell();
            var mytd_3=mytr.insertCell();
            var mytd_4=mytr.insertCell();
            var mytd_5=mytr.insertCell();
            mytd_1.innerHTML="<input type='text' name='myname"+i+"'/>";
            mytd_2.innerHTML="<input type='radio' name='mysex"+i+"' value='1'/>男<input type='radio' name='mysex"+i+"' value='2'/>女";
            mytd_3.innerHTML="<input type='checkbox' name='mylove"+i+"' value='1'/>上网<input type='checkbox' name='mylove"+i+"' value='2'/>篮球<input type='checkbox' name='mylove"+i+"' value='3'/>游泳";
            mytd_4.innerHTML="<select name='myjg"+i+"'><option value='1'>北京</option><option value='2'>河北</option><option value='3'>天津</option></select>";
            mytd_5.innerHTML="<input type='button' value='删除' onclick=\"delMyRow('"+i+"')\"/>";
            i++;
        }
        //删除当前行
        function delMyRow(j){
            var mytable = document.getElementById("mybody");
            var myrow = document.getElementById("tr"+j);
            mytable.deleteRow(myrow.rowIndex-1);
        }
        //删除所有行
        function delAllMyRow(){
            var mytable = document.getElementById("mybody");
            var rowlen=mytable.rows.length;
            for(var i=rowlen-1;i>=0;i--){
                mytable.deleteRow(i);
            }
        }
        </script>