JavaScript随机数组（数组、随机、取整、取值的过程）

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>随机五个数</title>
</head>
<body>
    <h1>第一种：正常数组</h1>
    <div id="demo"></div>
    <script type="text/javascript">
        var demo = document.getElementById('demo');//获取对象
        var arr = ['6666','9999','8888'];//数组
        var arrLength = arr.length;//获取数组长度
        var sj = Math.random()*arrLength;//随机
        var i = Math.floor(sj);//取整
        // 赋值
        demo.innerHTML=arr[i];//取数组里面的值（下标）
    </script>

    <h1>第二种写法：字符串数组</h1>
    <div id="demo2"></div>
    <script type="text/javascript">
        var demo2 = document.getElementById('demo2');
        var arr2 = "一一一,二二二,三三三";//字符串
        function num(d){
            var fenge = d.split(',');//分割字符串
            var arrLength2 = fenge.length;
            var sj2= Math.random()*arrLength2;
            var index = Math.floor(sj2);
            demo2.innerHTML = fenge[index];
        }
        num(arr2)

    </script>
</body>
</html>

效果图：

随机1-22：

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>

<body>
    <p id="demo"></p>
    <script>
        //    function RandomNumBoth(Min, Max) {
        //         var Range = Max - Min;
        //         var Rand = Math.random();
        //         var num = Min + Math.round(Rand * Range);
        //         return num;
        //     }
        // let arr = [];
        // for (let i = 0; i < 6; i++) {
        //     arr.push(`${parseInt(RandomNumBoth(1, 22))}-${RandomNumBoth(0, 1)}`)
        // }
        // let newArr = [...new Set(arr)];
        // if (arr.length === newArr.length) {
        //     alert("符合要求了")
        // } else {
        //     alert("有重复的")
        // }
        // console.log(arr)

        function RandomNumBoth(Min, Max) {
            var Range = Max - Min;
            var Rand = Math.random();
            var num = Min + Math.round(Rand * Range);
            return num;
        }

        let arr = [];
        for (let i = 0; i < 6; i++) {
            let sj = `${parseInt(RandomNumBoth(1, 22))}-${RandomNumBoth(0, 1)}`
            if (!arr.includes(sj)) {
                arr.push(sj)
            }
        }
        console.log(arr);




    </script>

</body>

</html>