JavaScript实现Checkbox全选与取消功能示例

<!DOCTYPE html> 
<html lang="en"> 
<head> 
<meta charset="UTF-8"> 
<title>Title</title> 
</head> 
<body> 
<input type="checkbox" onclick="quanxuan()">全选 
<input type="checkbox" name="nation">唱歌 
<input type="checkbox" name="nation">跳舞 
<input type="checkbox" name="nation">书法 
</body> 
<script type="text/javascript"> 
var k=0; 
function quanxuan(){ 
var s=document.getElementsByName("nation"); 
if(k%2==0) 
{ 
for(var i=0;i< s.length;i++) 
{ 
s[i].checked=true; 
} 
k++; 
} 
else { 
for(var j=0;j< s.length;j++) 
{ 
s[j].checked=false; 
} 
k++; 
} 
} 
</script> 
</html>