JS获取循环表格中input的值,该怎么处理

JS获取循环表格中input的值
请问我该如何获取到鼠标点击的tr行input的值呢？
现在获取到的是始终是第一条记录。。。。。。。

JScript code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->function popUserDetail(x){    var popUp = document.getElementById("popUserDetail");  var h = (x.rowIndex)*20;        popUp.style.top= 25 + h + "px";        popUp.style.left="142px";        popUp.style.width="200px";        popUp.style.height="100px";        popUp.style.visibility="visible";            var customerId = document.getElementsByTagName("input")[0].value;    alert (customerId);    }

Copy after login

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->           while ($records = mysql_fetch_array($rows))               {                   $arr = ct($records['uniqueid']);                  $fileLastUploadTime  = $arr[1];                    print       '                    <tr id="rIndex" onclick="popUserDetail(this)" onmousemove="hidePopUserDetail()">                    <input type="hidden" name="customerId" value="'.$records[" uniqueid>                     <input type="hidden" name="firstLogin" value="'.$records[" firstlogin>                     <input type="hidden" name="address" value="'.$records[" address>                                                             <td width="40px">'.st($records['lastT'],$fileLastUploadTime).'</td>                          <td width="100px">'.$records['barName'].'</td>                          <td width="160px">'.$records['lastLogin'].'</td>                          <td width="160px">'.date("Y-m-d H:i:s",$arr[1]).'</td>                          <td width="150px">'.$records['endTM'].'</td>                          <td width="40px">'.$arr[0].'</td>                          <td width="40px" style="border-right:0;">'.$records['version'].'</td>                          </tr>';                  }  print                  '                    <div class="popUserDetail" id="popUserDetail">                          <table>                          <tr>
<td id="">客户编号:</td>
<td id="cId"></td>
</tr>                                                                    <tr>
<td>客户地址:</td>
<td></td>
</tr>                          <tr>
<td>初次登陆:</td>
<td>备份周期:</td>
</tr>                          <tr>
<td>联系QQ:</td>
<td>联系电话:</td>
</tr>                          </table>                    </div>

Copy after login