单选按钮控制文本框是否可编辑

ILoveDOUZHOU

jsp文件中控制文本框是否可编辑的js代码
<script type="text/javascript">function gd() {var value = document.getElementById("radio").checked;if (!value) {document.getElementById("gdnr").disabled = true;} else {document.getElementById("gdnr").disabled = false;}}</script>
<s:form name="addForm" action="*" namespace="*" method="post" ><table>    <tr>        <td>   是否滚动广告：</td><td><input id="radio" type="radio" name="sfgd" value=1 checked="true"  />  是<input id="radio" type="radio" name="sfgd" value=0  />  否</td>   </tr>   <tr><td>        <s:textfield id="gdnr" label="滚动内容 " name="gdnr" value="%{gdnr}"onChange="return gd()" /></td>   </tr></table>