javascript 添加、删除、改变 css 样式名的实现方法

<script type="text/javascript">

// 说明：添加、移除、检测 className

// 整理：CodeBit.cn ( http://www.111cn.net )

function hasClass(element, className) {

var reg = new RegExp('(\s|^)'+className+'(\s|$)');

return element.className.match(reg);

}

function addClass(element, className) {

if (!this.hasClass(element, className))

{

element.className += " "+className;

}

}

function removeClass(element, className) {

if (hasClass(element, className)) {

var reg = new RegExp('(\s|^)'+className+'(\s|$)');

element.className = element.className.replace(reg,' ');

}

}

</script>

<style>
.unnamed1   {
background-image:   url(../images/botton.gif);
background-repeat:   no-repeat;
background-position:   center   center;
font-size:   14px;
line-height:   130%;
text-decoration:   none;
color:   #003399;
text-align:   center;
display:   list-item;
font-weight:   bold;

}
.unnamed2   {
background-attachment:   scroll;
background-image:   url(../images/botton1.gif);
background-repeat:   no-repeat;
background-position:   center   center;
font-size:   14px;
line-height:   130%;
color:   #FF0000;
text-decoration:   none;
font-weight:   bold;
text-transform:   capitalize;
font-style:   italic;
}
</style>
<script>
function   ChangeClass(obj)
{
      var   tb=document.getElementById( "tb ");
      var   tdn=tb.getElementsByTagName( "td ");
      for(var   i=0;i <tdn.length;i++)   {
      tdn[i].className= 'unnamed2 ';
      }
      obj.className= 'unnamed1 ';
}
</script>
<table   id=tb>
<tr> <td   class=unnamed2   onclick= "ChangeClass(this) "> 详细1 </td> </tr>
<tr> <td   class=unnamed2   onclick= "ChangeClass(this) "> 详细2 </td> </tr>
</table>