<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>全选反选示例</title>
<script>
function selectAll() {
var checkboxes = document.querySelectorAll('input[type="checkbox"]');
for (var i = 0; i < checkboxes.length; i++) {
checkboxes[i].checked = true;
}
}
function deselectAll() {
var checkboxes = document.querySelectorAll('input[type="checkbox"]');
for (var i = 0; i < checkboxes.length; i++) {
checkboxes[i].checked = false;
}
}
function toggleSelect() {
var checkboxes = document.querySelectorAll('input[type="checkbox"]');
for (var i = 0; i < checkboxes.length; i++) {
checkboxes[i].checked = !checkboxes[i].checked;
}
}
</script>
</head>
<body>
<h1>全选反选示例</h1>
<input type="checkbox" id="checkbox1">
<label for="checkbox1">选项1</label><br>
<input type="checkbox" id="checkbox2">
<label for="checkbox2">选项2</label><br>
<input type="checkbox" id="checkbox3">
<label for="checkbox3">选项3</label><br>
<button onclick="selectAll()">全选</button>
<button onclick="deselectAll()">取消选择</button>
<button onclick="toggleSelect()">反选</button>
</body>
</html>
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