多个fieldset，怎么通过button按钮同时只显示一个呢

Question

 <a class="mini-button" id="button3" style="" onclick="">用户名</a>
 <a class="mini-button" id="button4" style="" onclick="">最喜爱</a>


 <fieldset>
  <legend>用户名与密码:</legend>
  <input name="hiddenField" type="hidden" value="hiddenvalue" />
  <label for="username">用户名:</label>
  <input type="text" id="username" value="www.dreamdu.com" />
  <label for="pass">密码:</label>
  <input type="password" id="pass" />
 </fieldset>
 <fieldset>
  <legend>性别:</legend>
  <label for="boy">男</label>
  <input type="radio" value="1" id="sex" />
  <label for="girl">女</label>
  <input type="radio" value="2" id="sex" />
  <label for="sex">保密</label>
  <input type="radio" value="3" id="sex" />  
 </fieldset>
 <fieldset>
  <legend>我最喜爱的:</legend>
  <label for="computer">计算机</label>
  <input type="checkbox" value="1" id="fav" />
  <label for="trval">旅游</label>
  <input type="checkbox" value="2" id="fav" />
  <label for="buy">购物</label>
  <input type="checkbox" value="3" id="fav" />  
 </fieldset>




比如说这段代码，我想通过两个按钮来控制，点击第一个按钮时显示上面的，点击第二个按钮显示下面的，请问如何实现？

Answer 1

 <a class="mini-button" id="button3" style="" onclick="toogleFD('un')">用户名</a>
<a class="mini-button" id="button4" style="" onclick="toogleFD('favor')">最喜爱</a>
<script>
    function toogleFD(id) {
        id = document.getElementById(id);
        id.style.display = id.style.display == 'none' ? 'block' : 'none'
    }
</script>

<fieldset id="un">
    <legend>用户名与密码:</legend>
    <input name="hiddenField" type="hidden" value="hiddenvalue" />
    <label for="username">用户名:</label>
    <input type="text" id="username" value="www.dreamdu.com" />
    <label for="pass">密码:</label>
    <input type="password" id="pass" />
</fieldset>
<fieldset>
    <legend>性别:</legend>
    <label for="boy">男</label>
    <input type="radio" value="1" id="sex" />
    <label for="girl">女</label>
    <input type="radio" value="2" id="sex" />
    <label for="sex">保密</label>
    <input type="radio" value="3" id="sex" />
</fieldset>
<fieldset id="favor">
    <legend>我最喜爱的:</legend>
    <label for="computer">计算机</label>
    <input type="checkbox" value="1" id="fav" />
    <label for="trval">旅游</label>
    <input type="checkbox" value="2" id="fav" />
    <label for="buy">购物</label>
    <input type="checkbox" value="3" id="fav" />
</fieldset>