js 全选/反选
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>复选框（checkbox）全选/全不选/返选</title>
<style>
body,dl,dt,dd,p {
margin: 0;
padding: 0;
}
body {
font-family: Tahoma;
font-size: 12px;
}
label,input,a {
vertical-align: middle;
}
label {
padding: 0 10px 0 5px;
}
a {
color: #09f;
text-decoration: none;
}
a:hover {
color: red;
}
dl {
width: 120px;
margin: 10px auto;
padding: 10px 5px;
border: 1px solid #666;
border-radius: 5px;
background: #fafafa;
}
dt {
padding-bottom: 10px;
border-bottom: 1px solid #666;
}
dt label {
font-weight: 700;
}
p {
margin-top: 10px;
}
</style>
<script type="text/javascript">
window.onload = function() {
var oA = document.getElementsByTagName("a")[0];
var oInput = document.getElementsByTagName("input");
var oLabel = document.getElementsByTagName("label")[0];
var isCheckAll = function() {
for (var i = 1, n = 0; i < oInput.length; i++) {
oInput[i].checked && n++
}
oInput[0].checked = n == oInput.length - 1;
oLabel.innerHTML = oInput[0].checked ? "全不选" : "全选"
};
//全选/全不选
oInput[0].onclick = function() {
for (var i = 1; i < oInput.length; i++) {
oInput[i].checked = this.checked
}
isCheckAll()
};
//反选
oA.onclick = function() {
for (var i = 1; i < oInput.length; i++) {
oInput[i].checked = !oInput[i].checked
}
isCheckAll()
};
//根据复选个数更新全选框状态
for (var i = 1; i < oInput.length; i++) {
oInput[i].onclick = function() {
isCheckAll()
}
}
}
</script>
</head>
<body>
<dl>
<dt>
<input type="checkbox" id="checkAll" /><label>全选</label><a
href="javascript:;">反选</a>
</dt>
<dd>
<p>
<input type="checkbox" name="item" /><label>选项（一）</label>
</p>
<p>
<input type="checkbox" name="item" /><label>选项（二）</label>
</p>
<p>
<input type="checkbox" name="item" /><label>选项（三）</label>
</p>
<p>
<input type="checkbox" name="item" /><label>选项（四）</label>
</p>
<p>
<input type="checkbox" name="item" /><label>选项（五）</label>
</p>
<p>
<input type="checkbox" name="item" /><label>选项（六）</label>
</p>
<p>
<input type="checkbox" name="item" /><label>选项（七）</label>
</p>
<p>
<input type="checkbox" name="item" /><label>选项（八）</label>
</p>
<p>
<input type="checkbox" name="item" /><label>选项（九）</label>
</p>
<p>
<input type="checkbox" name="item" /><label>选项（十）</label>
</p>
</dd>
</dl>
</body>
</html>