案例：javascript案例     状态：可编辑再运行    进入竖版
 运行结果　
​x
 
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<html>
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<body>
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<img id="compman" src="/img/eg_compman.gif" alt="Computerman" />
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<br />
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​
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<script type="text/javascript">
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x=document.getElementsByTagName('img')[0];
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document.write("Image id: " + x.id);
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document.write("<br />");
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document.write("An alternate way: ");
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document.write(document.getElementById('compman').id);
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</script>
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​
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</body>
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</html>
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​