01.Document Object Model/03.01.CollectList.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<ul id="items">
    <li>first item</li>
    <li>second item</li>
    <li>third item</li>
</ul>
<textarea id="result"></textarea>
<br>
<button onclick="extractText()">Extract Text</button>
<script>
    function extractText() {
        let liItems = document.getElementById("items");
        let area = document.getElementById("result");
        area.value = "";
        let li = liItems.children;
        for (let i = 0; i < li.length; i++) {
             area.value += li[i].textContent + '\n';
        }
    }
</script>

</body>
</html>