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                        /JavaScript入門(mén)篇

沒(méi)有反應(yīng)，實(shí)在找不到原因了，煩請(qǐng)各位給看看啊

<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" Content="text/html; charset=utf-8" />
<title>javascript</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課程</h2>
? <div id="txt">
???? <h5>JavaScript為網(wǎng)頁(yè)添加動(dòng)態(tài)效果并實(shí)現(xiàn)與用戶交互的功能。</h5>
??????? <p>1. JavaScript入門(mén)篇，讓不懂JS的你，快速了解JS。</p>
??????? <p>2. JavaScript進(jìn)階篇，讓你掌握J(rèn)S的基礎(chǔ)語(yǔ)法、函數(shù)、數(shù)組、事件、內(nèi)置對(duì)象、BOM瀏覽器、DOM操作。</p>
??????? <p>3. 學(xué)完以上兩門(mén)基礎(chǔ)課后，在深入學(xué)習(xí)JavaScript的變量作用域、事件、對(duì)象、運(yùn)動(dòng)、cookie、正則表達(dá)式、ajax等課程。</p>
? </div>
?
? <form>
? 
???
??? <input type="button" value="改變顏色" onclick="changeColor()">
??? <input type="button" value="改變寬高" onclick="changehw()"/>
??? <input type="button" value="隱藏內(nèi)容" onclick="hiding()"/>
??? <input type="button" value="顯示內(nèi)容" onclick="showThem()"/>
??? <input type="button" value="取消設(shè)置" onclick="hehehe()"/>
? </form>
? <script type="text/javascript">
??? function changeColor(){
??????? var mychar=document.getElementById("txt");
??????? mychar.style.color="red"; }
???
??? function changehw(){
??????? var mychar=document.getElementById("txt");
??????? mychar.style.height="200px";
??????? mychar.style.width="400px";
??? }
???
??? function hiding(){
?????? var mychar=document.getElementById("txt");
?????? mychar.style.display="none";
??? }
??? function showThem(){
??????? var mychar=document.getElementById("txt");
??????? mychar.style.display="block";
??? }
??? function hehehe(){
?????? var mychar=document.getElementById("txt");
?????? var hehe=confirm("確定取消設(shè)置嗎？");
??????? if(hehe==true)
?????????? mychar.removeAttribute("style");
??????????
??? }
?? </script>
</body>
</html>