jq选择器 http://www.runoob.com/

$("p:not(.intro)").css("background-color","blue");      //p标签除了class=“intro”外的颜色....

与  $("p:visible").css("background-color","yellow")<选取所有可见的元素>;用法相反

 

 1)<input type="text" name="user" />

2)<input type="password" name="password" disabled="disabled" />

3)<select multiple="multiple">
  <option>Volvo</option>
  <option selected="selected">Saab</option>
  <option>Mercedes</option>
  <option>Audi</option>
</select>

4)<input type="radio" name="sex" value="male" checked="checked"/>