How to use arrays for random roll call-JS Tutorial-php.cn

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How to use arrays for random roll call

一个新手

Sep 11, 2017 am 10:18 AM

arrayconductrandom

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>随机点名简单版</title>
	<script>
	window.onload = function(){
		//0 - arr.length-1
		var arr = [&#39;宝宝&#39;,&#39;豆豆&#39;,&#39;慧新&#39;,&#39;洪红&#39;,&#39;黄黄&#39;,&#39;小子&#39;,&#39;杜度&#39;,&#39;方放&#39;,&#39;顾股&#39;,&#39;胡胡&#39;,&#39;谢写&#39;,&#39;蒋讲&#39;,&#39;陈美女&#39;];
		var name = document.getElementById(&#39;name&#39;);
		var btn = document.getElementById(&#39;namee&#39;);
		btn.onclick = function(){
			// 得到一个随机整数
			var idx = parseInt(Math.random()*arr.length);

			// 把取到的名字写入#name输入框
			name.value = arr[idx];
		}
	}
	
	</script>
</head>
<body>
	<input type="text" id="name">
	<button id="namee">随机点名</button>
</body>
</html>

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