哪位大佬幫我看看,為什么點(diǎn)擊按鈕沒(méi)有任何反應(yīng)?
<!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>
? <!--當(dāng)點(diǎn)擊相應(yīng)按鈕,執(zhí)行相應(yīng)操作,為按鈕添加相應(yīng)事件-->
??? <input type="button" value="改變顏色" onclick="change()"> ?
??? <input type="button" value="改變寬高" onclick="hw()" >
??? <input type="button" value="隱藏內(nèi)容" onclick="hid()">
??? <input type="button" value="顯示內(nèi)容" onclick="display()">
??? <input type="button" value="取消設(shè)置" onclick="cancel()">
? </form>
? <script type="text/javascript">
//定義"改變顏色"的函數(shù)
? function change(){
????? var obj= document.getElementById("txt");
????? obj.style.color = "red";
????? obj.style.backgroundColor = "blue";
? }
//定義"改變寬高"的函數(shù)
??? function hw()
??? {
??????? var obj = document.getElementById("txt");
??????? obj.style.weight="200px";
??????? obj.style.height="100px";
??? }
//定義"隱藏內(nèi)容"的函數(shù)
?? ?
??? function hid(){
??????? var obj = document.getElementById("txt");
??????? obj.style.display = "none";
??? }
//定義"顯示內(nèi)容"的函數(shù)
??? function display(){
??????? var obj = document.getElementById("txt");
??????? obj.style.display = "block";
??? }
//定義"取消設(shè)置"的函數(shù)
??? function cancel(){
??????? var obj = confirm("是否取消設(shè)置");
??????? if(obj == true){
??????????? document.getElementById("txt").removeAttribute("style");
??????? else?? ?
??????????? return false;
??????? }
??? }
? </script>
</body>
</html>
2019-05-19