For loop return just last item of array

July 24, 2022

I don’t understand why I’m getting as output just the last item of the loop. I would like to obtain a list with every result, however the code does only return le last item of myArray. Can anyone help?

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

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

    

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

</script>

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

>Solution :

You have to replace =+ with +=.

a =+ b; is equivalent to a = +b; which is just a way of casting b to number, that is, type coercion.

Check now by running this snippet with your code:

let myArray = [5, 7, 9]

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

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

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