console 命令行工具 X clear
console
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	<meta charset="utf-8">
	<title>菜鸟教程(runoob.com)</title>
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	<p>实例在 window 对象中使用 addEventListener() 方法。</p>
	<p>尝试重置浏览器的窗口触发 "resize" 事件句柄。</p>
	<p id="demo"></p>
	<script>
		window.addEventListener("resize", function(){
    document.getElementById("demo").innerHTML = Math.random();
});

	</script>

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