前端学习笔记之多选框

<!DOCTYPE html>
<html lang=”en”>

<head>
    <meta charset=”UTF-8″>
    <meta name=”viewport” content=”width=device-width, initial-scale=1.0″>
    <title>多选框</title>
    <style>
        * {
            margin: 0px;
            padding: 0px;
        }

        ul {
            list-style: none;
            display: flex;
        }
    </style>
</head>

<body>
    <form action=””>
        <ul>
            <li>
                西瓜<input type=”checkbox”>
            </li>
            <li>
                苹果<input type=”checkbox”>
            </li>
            <li>
                葡萄<input type=”checkbox”>
            </li>
            <li>
                榴莲<input type=”checkbox”>
            </li>
        </ul>
        <input type=”button” value=”全选” id=”all_btn”>
        <input type=”button” value=”全不选” id=”notall_btn”>
        <input type=”button” value=”反选” id=”invert”>
    </form>
    <script>
        let all_btn = document.getElementById(“all_btn”);
        let notall_btn = document.getElementById(“notall_btn”);
        let invert = document.getElementById(“invert”);
        let check = document.querySelectorAll(`input[type=”checkbox”]`);
        all_btn.onclick = function () {
            check.forEach((item) => {
                item.checked = true;
            })
        };
        notall_btn.onclick = function () {
            check.forEach((item) => {
                item.checked = false;
            })
        };
        invert.onclick = function () {
            check.forEach((item) => {
                // item.checked ? item.checked = true : item.checked = false;
                item.checked=!item.checked;
            })
        };
    </script>
</body>