為什么不輸出JavaScript里的內(nèi)容？
<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>無標(biāo)題文檔</title>
</head>
<body>
? <p id="intro">我的課程</p>?
? <ul>?
??? <li title="JS">JavaScript</li>?
??? <li title="JQ">JQuery</li>?
??? <li title="">HTML/CSS</li>?
??? <li title="JAVA">JAVA</li>?
??? <li title="">PHP</li>?
? </ul>?
? <h1>以下為li列表title的值,當(dāng)title為空時，新設(shè)置值為"WEB前端技術(shù)："</h1>
<script type="text/javascript">
? var Lists=document.getElementsByTagName("li");
? for (var i=0; i<Lists.length;i++)
? {
??? var text = lists[i].getAttribute("title");
??? document.write(text +"<br>");
??? if(text=="")
??? {
??? lists[i].setAttribute("title","web前端技術(shù)");
??? document.write(Lists[i].getAttribute("title")+"<br>");
??? }
? }
</script>
</body>
</html>
2016-11-16
var text = lists[i].getAttribute("title");
Lists[i] ? 第一個字母要大寫
2016-11-16
還有輸出最好都放入判斷條件中
if?(text?==?"")?{ ????Lists[i].setAttribute("title","web前端技術(shù)"); ????document.write(Lists[i].getAttribute("title")+"<br>"); ????} }?else?{ ????document.write(text?+"<br>"); }