40 lines
991 B
HTML
40 lines
991 B
HTML
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<!DOCTYPE html>
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<html>
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<head>
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<meta charset="utf-8" />
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<meta name="author" content="flykhan" />
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<meta name="keywords" content="c c++ 物联网" />
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<title>DOM操作</title>
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<style>
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.large_span {
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font-size: 25px;
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color: red;
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padding: 1px;
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border: 1px solid greenyellow;
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margin: 5px;
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}
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</style>
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</head>
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<body>
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<span name="sex">a</span>
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<span name="sex">b</span>
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<span class="item">c</span>
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<span class="item">d</span>
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<span class="item">e</span>
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<script>
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// js 的延迟器， 2000 毫秒之后执行匿名函数（箭头函数）
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setTimeout(() => {
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// 返回的是NodeList（节点列表）
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// 获取所有的span标签，添加一个新的类名 large_span
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let spans3 = document.getElementsByTagName("span");
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for (let i in spans3) {
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spans3[i].className += " large_span";
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}
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}, 2000);
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</script>
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</body>
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</html>
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