​x
 
<html>
<head>
<script type="text/javascript">
function check()
{
document.getElementById("myCheck").checked=true
}
​
function uncheck()
{
document.getElementById("myCheck").checked=false
}
</script>
</head>
​
<body>
<form>
<input type="checkbox" id="myCheck" />
<input type="button" onclick="check()" value="选定复选框" />
<input type="button" onclick="uncheck()" value="取消选定复选框" />
</form>
</body>
​
</html>
​