w3school事件參考：http://www.w3school.com.cn/jsref/dom_obj_event.asp
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>鍵盤事件</title>
<script>
window.onload = function() {
document.onkeydown = function(event) {
event = event || window.event;
// console.log(event.keyCode);
//判斷是否按下快捷鍵ctrl + c
if(event.ctrlKey && event.keyCode===67){
alert('複製');
}
}
}
</script>
</head>
<body>
<!--<input type="text" />-->
</body>
</html>