题解 | #全选#
全选
https://www.nowcoder.com/practice/84b89f326e3c4e96bacb63296e84623a
本地能过 但是可能不是题目所需要的，所以在线编辑器通过不了
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
</head>
<style>
ul {
list-style: none;
}
</style>
<body>
<ul>
<li>全选<input type='checkbox' id='all' onchange="handleAllChange(this.checked)"></li>
<li>Java<input type='checkbox' class='item' onchange="handleItemChange()"></li>
<li>javaScript<input type='checkbox' class='item' onchange="handleItemChange()"></li>
<li>C++<input type='checkbox' class='item' onchange="handleItemChange()"></li>
<li>python<input type='checkbox' class='item' onchange="handleItemChange()"></li>
<li>.net<input type='checkbox' class='item' onchange="handleItemChange()"></li>
</ul>
<script>
// 补全代码
let itemList = Array.from(document.getElementsByClassName('item'));
let all = document.getElementById('all');
function handleItemChange() {
for (let index = 0; index < itemList.length; index++) {
if (!itemList[index].checked) {
all.checked = false;
return;
}
all.checked = true;
}
}
function handleAllChange(val) {
if (val) {
for (let index = 0; index < itemList.length; index++) {
itemList[index].checked = true;
}
} else {
for (let index = 0; index < itemList.length; index++) {
itemList[index].checked = false;
}
}
}
</script>
</body>
</html>
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