要素の書き換え

var 変数名

[renshu-33.html]

<!DOCTYPE html>
<html lang="ja">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
</head>
<body>

    <div class="eee">
        <ul>
            <li class="fff">1つ目</li>
            <li class="fff">2つ目</li>
            <li class="fff">3つ目</li>
        </ul>

        <input type="button" id="myfunc" value="ぼたん">
    </div>
    
</body>
</html>

<script>
    const myfunc = document.getElementById("myfunc");

    myfunc.onclick = function (){
        var fff = document.querySelector(".fff");
        fff.textContent = "11つ目";

    }
    

</script>