效果图：
<!DOCTYPE html>
<html lang="zh">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>随机从数组中取某一个值</title>
</head>
<body>
</body>
<script>
var items = ['1','2','3','4'];
var vaule = items[Math.floor(Math.random()*items.length)];
console.log(vaule,'随机从数组中取到的某一个值');
</script>
</html>