如何不使用document.getElementById()在HTML中直接显示JS数组元素

我用JavaScript写了一个生成数组的函数，数组生成后想在HTML里展示部分元素，但不想用document.getElementById()方法，请问能不能直接在HTML里选取数组元素展示？

原有实现代码 #

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Distance calculator</title>

<script>
let myArray = [5, 7, 9]
var soluzioni =[]
    

function calcolo(){
    for(let i=0; i<myArray.length; i++){
        var y = myArray[i];
        var risultato = y*y;
        soluzioni.push(risultato);
    document.getElementById('Calcolo').innerHTML =+ soluzioni[0] + "<br>";    
    }
     
}
    

</script>

    
</head>
<body>
    <div id="posizione">
        <button onclick="calcolo();"> calcola</button>
    </div>
    <br>
    
    <div id="Calcolo">
        
    </div>

</body>
</html>

期望实现的形式 #

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Distance calculator</title>

<script>
let myArray = [5, 7, 9]
var soluzioni =[]
    

function calcolo(){
    for(let i=0; i<myArray.length; i++){
        var y = myArray[i];
        var risultato = y*y;
        soluzioni.push(risultato);   
    }
     
}
    

</script>

    
</head>
<body>

    <div id="posizione">
        <button onclick="calcolo();"> calcola</button>
    </div>
    <br>
    
    <div id="Calcolo">
        <p> soluzioni[0] </p>
    </div>

</body>
</html>

直接在HTML里写soluzioni[0]是行不通的，因为HTML是静态标记语言，本身无法识别和解析JavaScript变量。不过你可以用以下几种替代方案，不用依赖document.getElementById()：

1. 直接引用元素ID变量（全局作用域下） #

浏览器会自动把带有id的DOM元素挂载到window对象上，你可以直接用元素的id作为变量名来操作DOM：

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Distance calculator</title>

<script>
let myArray = [5, 7, 9]
var soluzioni =[]
    

function calcolo(){
    for(let i=0; i<myArray.length; i++){
        var y = myArray[i];
        var risultato = y*y;
        soluzioni.push(risultato);   
    }
    // 直接用元素id"Calcolo"作为变量
    Calcolo.innerHTML = soluzioni[0];
}
    

</script>

    
</head>
<body>
    <div id="posizione">
        <button onclick="calcolo();"> calcola</button>
    </div>
    <br>
    
    <div id="Calcolo">
    </div>

</body>
</html>

2. 使用document.querySelector()选择元素 #

用querySelector()替代getElementById()，语法更灵活，也能实现相同的效果：

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Distance calculator</title>

<script>
let myArray = [5, 7, 9]
var soluzioni =[]
    

function calcolo(){
    for(let i=0; i<myArray.length; i++){
        var y = myArray[i];
        var risultato = y*y;
        soluzioni.push(risultato);   
    }
    // 通过选择器获取元素并修改内容
    document.querySelector('#Calcolo').innerHTML = `<p>${soluzioni[0]}</p>`;
}
    

</script>

    
</head>
<body>
    <div id="posizione">
        <button onclick="calcolo();"> calcola</button>
    </div>
    <br>
    
    <div id="Calcolo">
    </div>

</body>
</html>

3. 使用前端框架实现数据绑定 #

如果不想手动操作DOM，可借助Vue、React这类前端框架，它们支持数据与视图的双向绑定，直接在HTML中通过插值语法展示数组元素：
（以Vue为例）

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Distance calculator</title>
<script src="https://cdn.jsdelivr.net/npm/vue@2"></script>
</head>
<body>
    <div id="app">
        <div id="posizione">
            <button @click="calcolo"> calcola</button>
        </div>
        <br>
        
        <div id="Calcolo">
            <p>{{ soluzioni[0] }}</p>
        </div>
    </div>

    <script>
    new Vue({
        el: '#app',
        data: {
            myArray: [5, 7, 9],
            soluzioni: []
        },
        methods: {
            calcolo() {
                this.soluzioni = this.myArray.map(num => num * num);
            }
        }
    })
    </script>
</body>
</html>

内容的提问来源于stack exchange，提问作者user13918655