那么今天的内容是 callback 回调函数的使用和 基础

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
        <title></title>
        <script src="js/jquery.js"></script>
    </head>
    
<style>
body{font-family: "微软雅黑";width: 980px; margin: 0 auto; text-align: center;}
    .box{
        width: 300px;
        height: 300px;
        background: green;
        border: 1px solid #e6e6e6;
        margintop: 50px;
        line-height: 200px;
        position: absolute;
    }
button{
    border: none;
    background: green;    
    width: 100px;
    height: 50px;
    line-height: 50px;
    color: #fff;
    font-size: 16px;
    margin-top: 50px;
    }
</style>
    
    <body>
        <button>点击开始动画</button>
        
        <div class="box" ></div>
        
        <script> 
            $(document).ready(function(){
              $("button").click(function(){
                var div=$(".box");
                div.animate({height:‘200px‘,opacity:‘0.4‘},"slow");
                div.animate({width:‘200px‘,opacity:‘0.8‘},"slow");
                div.animate({height:‘100px‘,opacity:‘0.4‘},"slow");
                div.animate({width:‘100px‘,opacity:‘0.8‘},"slow");
                div.animate({right:‘100px‘,opacity:‘0.8‘},"slow");
                div.animate({bottom:‘100px‘,opacity:‘0.8‘},"slow");
                div.animate({left:‘100px‘,opacity:‘0.8‘},"slow");
                div.animate({top:‘100px‘,opacity:‘0.8‘},"slow",function(){
                    alert("The paragraph is over");
                });
              });
            });
        </script> 

        <script>
            $(document).ready(function(){
                $("button").click(function(){
                    var div=$(".box");
                        div.animate({height:‘300px‘,opacity:‘0.4‘},"slow");
                        div.animate({width:‘300px‘,opacity:‘0.8‘},"slow");
                        div.animate({height:‘100px‘,opacity:‘0.4‘},"slow");
                        div.animate({width:‘100px‘,opacity:‘0.8‘},"slow",function(){
                    alert("The paragraph is over");
              　　　　  });
                    });
                });
            });
        </script>
        
    </body>
</html>