如何取得table的行列数

Question

    <table style="width: 100%;">
        <tr>
            <td>
                <a href="javascript:void(0)" onclick="clickA()">clickme</a>
            </td>
            <td>
                &nbsp;
            </td>
            <td>
                &nbsp;
            </td>
        </tr>
    </table>
        function clickA() {
            var td = this.parent;
            alert(td.tagName);
    }
table的单元格里是anchor，点这个anchor(或其它控件)，如何得到当前行列？

Answer 1

function getinfo() {
            var e = event.srcElement;
            if (e.tagName == "TD") {
                var r = e.parentElement.rowIndex + 1;
                var c = e.cellIndex + 1;
                document.getElementById("info").innerText = "当前行号： " + r + "   列号： " + c;
            }
        }

Answer 2

<script>
function clickA()
{
var mytable = document.getElementById("mytable");
alert(mytable.getElementsByTagName("tr").length);
}
</script>
<table id="mytable" style="width: 100%;">
        <tr>
            <td>
                <a href="javascript:void(0)" onclick="clickA()">clickme</a>
            </td>
            <td>
                &nbsp;
            </td>
            <td>
                &nbsp;
            </td>
        </tr>
    </table>