Question

我想随机地从数组创建一个数组，但我开始使用javascript。这是我的问题。

<p id "demo1"></p>
<p id "demo2"></p>
<p id "demo3"></p>

 CREATE TABLE #FilesList(ID INT IDENTITY(1,1), FileName VARCHAR(1000),Depth INT,isFile INT)
    INSERT INTO #FilesList
    EXEC xp_dirtree @FilePath, 1, 1

我想我必须将双引号 - “house” - 字符串转换为object - house - 转换为var并在输入系统之前？

Answer 1

我不是100％肯定你在这里问的是什么，但我相信你想要的行为可以用2d数组完成 -

const t = [["red","blue","orange","black"], ["silver", "gold", "cooper","plastic"], ["marble","oak","yep","pine"], ["computer","mobile","mac","tablet"]]

const [rand1, rand2] = [Math.floor(Math.random() * t.length), Math.floor(Math.random() * t[0].length)]
console.log(t[rand1][rand2])

Answer 2

您可以使用switch函数来获取对象引用，但它可能会导致毛病问题，因此最好使用其他选项，例如//array var t = ["house","pen","table","electronic"]; var house = ["red","blue","orange","black"]; var pen = ["silver", "gold", "cooper","plastic"]; var table = ["marble","oak","yep","pine"]; var electronic = ["computer","mobile","mac","tablet"]; var w = Math.floor(Math.random() * 3); // random type index (0 to 3) var x = t[w]; // name of the random type var y = Math.floor(Math.random() * 3); // random option (0 to 3) switch (w) { // use the appropriate object based on type index case 0: z=house[y]; break; case 1: z=pen[y]; break; case 2: z=table[y]; break; case 3: z=electronic[y]; break; } console.log(w, z); var z = z + ' ' + x // appending "house" to color console.log(z); document.getElementById("demo1").innerHTML=z;语句：

＆＃13;

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<p id="demo2"></p>
<p id="demo3"></p>

＆＃13;

<audio id="my_audio" >
              <source src="bark.mp3" type="audio/mpeg">
            </audio>
            <audio id="my_audio2">
              <source src="roar.mp3" type="audio/mpeg">
            </audio>

            <audio id="my_audio3">
              <source src="hoot.mp3" type="audio/mpeg">
            </audio>

    <script type="text/javascript">
        $(document).ready(function() {
            $("#my_audio").get(0).play();

            $("#my_audio").bind("ended", function(){ 
                setTimeout(function() { $("#my_audio2").get(0).play(); },2000);

                $("#my_audio2").bind("ended", function(){ 
                    setTimeout(function() { $("#my_audio3").get(0).play(); },2000);                 
            });    
            });    
    });    

    </script>

＆＃13;

Answer 3

如果这是您正在寻找的内容，我不太清楚，但一种解决方案可能是构建您的数据，以便更容易获得：

const items = {
  house: ["red","blue","orange","black"],
  pen: ["silver", "gold", "cooper","plastic"],
  table:  ["marble","oak","yep","pine"],
  eletro: ["computer","mobile","mac","tablet"]
}

const randomChoice = list => list[Math.floor(list.length * Math.random())]

const randomObject = (items) => {
  const itemType = randomChoice(Object.keys(items))
  const modifier = randomChoice(items[itemType])
  return `${modifier} ${itemType}`
}

randomObject(items) //=> "marble table" or "plastic pen", etc.

更新

评论要求选择某种类型的随机元素。这种变化将允许：

const randomOfType = (items, itemType) => {
  const modifier = randomChoice(items[itemType])
  return `${modifier} ${itemType}`
}

const randomObject = (items) => randomOfType(items, randomChoice(Object.keys(items)))

randomOfType(items, 'table') //=> "oak table" or "marble table", etc.

Javascript字符串对象错误？随机数组var没有aloowed

3 个答案:

更新