检测旋钮所在行

检测按钮所在行
我想通过点击button触发change（this）事件，获取按钮所在行的id，然后调用changeTotext()方法，使所需要的单元格变换成文本框来进行修改数据，function change（obj）{}方法不会写。

<br>
nbsp;html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"><br>
<br>
<br>
<meta><br>
<title>Insert title here</title><br>
<script><br />
         function showtd(num) {            <br />
             document.getElementById("bg"+num).style.display = "none";<br />
             document.getElementById("show"+num).style.display = "block";<br />
         }<br />
         function hidetd(num) {<br />
             document.getElementById("bg"+num).style.display = 'block';<br />
             document.getElementById("show"+num).style.display = 'none';<br />
         }<br />
<br />
         function changeTotext()  <br />
         {   <br />
             var tdValue = obj.innerText;  <br />
             obj.innerText = "";  <br />
             var txt = document.createElement("input");  <br />
             txt.type = "text";  <br />
             txt.value = tdValue;  <br />
             txt.id = "_text_000000000_";  <br />
             txt.setAttribute("className","text");  <br />
             obj.appendChild(txt);  <br />
             txt.select();   <br />
         }  <br />
<br />
         function change(obj){<br />
            <br />
             <br />
             }<br />
<br />
            function mouseup(){ <br />
                if (document.getElementById("sort_t") && event.srcElement.id != "sort_t") <br />
                { <br />
                    var obj = document.getElementById("sort_t").parentElement; <br />
                var txtValue = document.getElementById("sort_t").value; <br />
                obj.innerText = txtValue; <br />
                }  <div class="clear">




            </script>