localStorage_留言板（储存功能）

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>留言本</title>
<script src="js/jquery-3.2.1.min.js"></script>
<script type="text/javascript">
   $(function(){
       //本地留言板内容不为空
       if(localStorage.getItem("k_con")!=null){
           "k_con",$("#dCon").html(localStorage.getItem("k_con"));
       }
   });
   function PostClick(){
       var trCon=$("#trCon").val();
       //将获取的内容直接加到给定的div中
       $("#dCon").append("<div>"+trCon+"</div>");
       //将留言板内容存入本地
       localStorage.setItem("k_con",$("#dCon").html());
   }
</script>

</head>
<body>
   <div><textarea id="trCon" cols="30" rows="8"></textarea></div>
   <div><input type="button" value="发表" onclick="PostClick();"> <input type="button" value="清除"> </div>
   <div id="dCon"></div>
</body>
</html>