方式1:
<?php
<div>
<input type="radio" name="a1" value="1" checked="true" onclick="t2.style.display='none';" />大类
<input type="radio" name="a1" value="2" onclick="t2.style.display='block';" />小类
</div>
<div>
<select name="t1" id="t1">
<option>1111111</option>
<option>1111111</option>
<option>1111111</option>
</select>
<select name="t2" id="t2" style="display:none;">
<option>2222222</option>
<option>2222222</option>
<option>2222222</option>
</select>
</div>
?>
方式2:
<?php
<div>
<input type="radio" name="a11" value="1" checked="true" onclick="t21.disabled=true;" />大类
<input type="radio" name="a11" value="2" onclick="t21.disabled=false;" />小类
</div>
<div>
<select name="t11" id="t11">
<option>1111111</option>
<option>1111111</option>
<option>1111111</option>
</select>
<select name="t21" id="t21" disabled="true">
<option>2222222</option>
<option>2222222</option>
<option>2222222</option>
</select>
</div>
?>
