添加删除表格的JS写法

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<title>Form Object example</title>
<head>
    <script language="javascript">
        function delrow1() {
            var oElement = event.srcElement;
            while (oElement.tagName != "TR") {
                oElement = oElement.parentElement;
            }
            var oTBody = oElement.parentElement;
            oTBody.removeChild(oElement);
        }

        function delrow2()//刪除当前行
        {
            var currRowIndex = event.srcElement.parentNode.parentNode.rowIndex;
            document.all.yltable.deleteRow(currRowIndex); //table10--表格id
        }
        function insertrow1() //增加的一行方法1
        {
            var newnode = document.getElementById('yltable').lastChild.cloneNode(true);
            document.getElementById('yltable').appendChild(newnode);
        }

        function insertrow2() //增加的一行方法2
        {
            var newRow = document.all.yltable.insertRow(-1);
            var j_1 = document.all.yltable.rows.length;
            var newcell = newRow.insertCell();
            newRow.bgColor = '#FFFFFF';
            newcell.align = 'center';
            newcell.innerHTML = "" + j_1 + "";

newcell = newRow.insertCell();
newRow.bgColor = '#FFFFFF';

newcell.align = 'center';
newcell.innerHTML = "<input type='text' name='ylText" + j_1 + "' />";

newcell = newRow.insertCell();
newRow.bgColor = '#FFFFFF';

newcell.align = 'center';

newcell.innerHTML = '<input name="button3" type="button" onClick="delrow1()" value="删除1"> <input name="button3" type="button" onClick="delrow2()" value="删除2">';

document.all.yltable.focus();

}

        function inserttable() {
            var newnode = document.getElementById('yltable').cloneNode(true);
            document.getElementById('ylform').appendChild(newnode);
        }
    </script>
</head>
<body>
    <form name="ylform" >
                    </div>
                </td>
            </tr>
        </tbody>
    </table>
    </form>
</body>
</html>