Detailed explanation of the usage of Attr in JS

<script type="text/javascript" src="js/jquery-1.8."></script>
<script type="text/javascript">
  $(document).ready(function(){
    $("#btn").click(function(){
      //Use attr(name) to get the attribute value:      alert($("p").attr("title"));//Your favorite fruit is.      alert($("ul li:eq(1)").attr("title"));//Orange juice      alert($("ul li:eq(1)").attr("alt"));//123
      //Use attr(name, value) to change the attribute value:      //$("ul li:eq(1)").attr("title", "or?");//Change the value of the title of the second li      //Use attr(name, fn) to set the function value of the attribute      $("ul li:eq(1)").attr("title", function(){
          return "I don't believe it";
      });//Change the value of the title of the second li      alert($("ul li:eq(1)").attr("title"));//I don't believe it      //Use attr(name, properties) to set an object in the form of "name/value" to the attributes of all matching elements      $("ul li:eq(1)").attr({title: "First", alt: "Second"});
      alert($("ul li:eq(1)").attr("title"));//The first      alert($("ul li:eq(1)").attr("alt"));//The second    });
  });
</script>
<p title="Your favorite fruit is.">Your favorite fruit is？</p>
<ul>
  <li title="Apple juice">apple</li>
  <li title="Orange Juice" name="tasty" alt="123">tangerine</li>
  <li title="Pineapple juice">Pineapple</li>
</ul>
<input type="button" value="Click" />