日期:2014-05-16  浏览次数:20408 次

一个评分控件的错误,请帮忙改正一下
[code=JScript][/code]
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head>
  <title>无标题页</title>
  <script type="text/javascript">
  function initEvent(){
  var table=document.getElementById("Gread");
  var tds=table.getElementsByTagName("td");
  for(var i=0;i<tds.length;i++){
  var td=tds[i];
  td.onclick=changeColor;
  td.style.cursor="pointer";
  }
  }
  function changeColor(){
  var table=document.getElementById("Gread");
  var tds=table.getElementsByTagName("td");
  var index=indexof(tds,this);
  for(var i=0;i<=index;i++){
  var td=tds[i];
  td.style.background="red";
  }
  for(var j=index+1;j<=tds.length;j++){//5个星星时候怎么办
  var td=tds[i];
  td.style.background="white";
  }
  }
  function indexof(arry,element){
  for(var i=0;i<arry.length;i++){
  if(arry[i]==element){
  return i;
  }  
  }
  }
  </script>
</head>
<body onload="initEvent()">
<table id="Gread">
  <tr>
  <td>
  ?
  </td>
  <td>
  ?
  </td>  
  <td>
  ?
  </td>
  <td>
  ?
  </td>
  <td>
  ?
  </td>
  </tr>
</table>
</body>
</html>
//Line: 26
//Error: Unable to get value of the property 'style': object is null or undefined(这个是网页的错误提示请问我应该怎么改啊!)

------解决方案--------------------
JScript code
for (var j = index + 1; j <= tds.length; j++) {//5个星星时候怎么办
               var td = tds[i];
               if (i <=4) { td.style.background = "white"; }
               else {return false;}