判断checkbox对应的值

<Script Language="JavaScript">
     function check(){
        var oInput = document.all.tags('INPUT');
        for(var i=0;i<=oInput.length-1;i++){
            if(oInput(i).type=='checkbox' && oInput(i).checked && toTr(oInput(i)).cells(toTr(oInput(i)).cells.length-1).innerText=='PE'){
              window.alert('表格第'+toTr(oInput(i)).rowIndex+'行有PE!!!');
            }            
        }
     }
     function toTr(oElement){
        try{
             while(oElement.tagName!='TR'){
                 oElement = oElement.parentElement;
             }
             return(oElement);
        }catch(error){
             window.alert('复选框没有在表格中！');
        }
     }
</Script>
<table width="30%"  border="1" align="center" cellpadding="1" cellspacing="1">
  <tr bgcolor="#CCCCCC">
    <td width="24%"><div align="center">checkbox</div></td>
    <td width="42%"><div align="center">id</div></td>
    <td width="34%"><div align="center">statu</div></td>
  </tr>
  <tr>
    <td><div align="center">
      <input type="checkbox" name="checkbox" value="11">
    </div></td>
    <td><div align="center">11</div></td>
    <td><div align="center">PE</div></td>
  </tr>
  <tr>
    <td><div align="center">
      <input type="checkbox" name="checkbox2" value="22">
    </div></td>
    <td><div align="center">22</div></td>
    <td><div align="center">PE</div></td>
  </tr>
  <tr>
    <td><div align="center">
      <input type="checkbox" name="checkbox22" value="33">
    </div></td>
    <td><div align="center">33</div></td>
    <td><div align="center">AE</div></td>
  </tr>
  <tr>
    <td><div align="center">
      <input type="checkbox" name="checkbox23" value="44">
    </div></td>
    <td><div align="center">44</div></td>
    <td><div align="center">AE</div></td>
  </tr>
  <tr>
     <td colspan="3" align="center"><input type="button" value="检查选择" onclick="check();"></td>
  </tr>
</table>