                        课程
                    
                        /前端开发
                        
                            /JavaScript
                        
                        /JavaScript入门篇

拿下供参考

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>编程挑战</title>
    <style type="text/css">
        body{font-size: 12px;}
        #txt{
            height: 400px;
            width: 600px;
            border: #333 solid 1px;
            padding: 5px;
        }
        p{
            line-height: 18px;
            text-indent: 2em;
        }
    </style>
</head>
<body>
    <h2 id="con">JavaScript课程</h2>
    <div id="txt">
        <h5>JavaScript为网页添加动态效果并实现与用户交互的功能。</h5>
        <p>1.JavaScript入门篇,让不懂JS的你快速了解JS。</p>
        <p>2.JavaScript进阶篇,让你掌握JS的基础语法、函数、数组、事件、内置对象、DOM浏览器、DOM操作。</p>
        <p>3.学完以上两门基础课后,再深入学习JavaScript的变量作用域、事件、对象、运动、cookie、正则表达式、Ajax课程等。</p>
    </div>
    <form>
        <input type="button" value="改变颜色" onclick="set.changeColor()">
        <input type="button" value="改变宽高" onclick="set.changeSize()">
        <input type="button" value="隐藏内容" onclick="set.objHide()">
        <input type="button" value="显示内容" onclick="set.objShow()">
        <input type="button" value="取消设置" onclick="set.offSet()">
    </form>
    <script type="text/javascript">
        var txt=document.getElementById("txt");
        var set={
            changeColor:function(){
                txt.style.color="red";
                txt.style.background="#ccc";
            },
            changeSize:function(){
                txt.style.width="300px";
                txt.style.height="300px";
            },
            objHide:function(){
                txt.style.display="none";
            },
            objShow:function(){
                txt.style.display="block";
            },
            offSet:function(){
                var message=confirm("你确定要重置所有设置么？");
                if(message==true){
                    txt.removeAttribute('style');
                }
            }
        }
    </script>
</body>
</html>