<input type="checkbox" id="che" checked>
<input type="button" id="btn1" value="反選">
<script>
var oche=document.getElementById('che');
var obtn1=document.getElementById('btn1');
obtn1.οnclick=function(){
//先獲取複選框當前的選中狀態
//console.log(oRadio.checked);
//或者 oRadio.checked ? oRadio.checked = false : oRadio.checked = true;
oche.checked=!oche.checked;
}
</script>
實現效果如下