<!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>
</html>