修改方法：修改搜索页模板，找到下面这段代码：

<tr>                      <td align="right">文章栏目:</td>                      <td><select name=’ClassID’><script language=’javascript’ src=’/Announce/JS/ShowClass_Option.js’></script></select></td>              </tr>

改成：

<tr>                      <td align="right">文章栏目:</td>                      <td><select name=’ClassID’><option value=’0’>所有栏目</option><script language=’javascript’ src=’/Announce/JS/ShowClass_Option.js’></script></select></td>              </tr>

即可。