javascript 如何捕获键盘事件来自哪些键？
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/6504914/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
How can I capture keyboard events are from which keys?
提问by Vimal Basdeo
I googled and got the following codes on the Net.However, when I press a keyboard key,it is not displaying me an alert box. I want to get which character I have pressed in the alert box. How do I fix this?
我在网上搜索并获得了以下代码。但是，当我按下键盘键时，它没有显示警告框。我想知道我在警告框中按下了哪个字符。我该如何解决？
<script type="text/javascript">
var charfield=document.getElementById("char")
charfield.onkeydown=function(e){
var e=window.event || e;
alert(e.keyCode);
}
</script>
</head>
<body id="char">
</body>
</html>
回答by Tim Down
If you want to get the character typed, you must use the keypressevent rather than the keydownevent. Something like the following:
如果要获得键入的字符，则必须使用keypress事件而不是keydown事件。类似于以下内容：
var charfield = document.getElementById("char");
charfield.onkeypress = function(e) {
e = e || window.event;
var charCode = (typeof e.which == "number") ? e.which : e.keyCode;
if (charCode > 0) {
alert("Typed character: " + String.fromCharCode(charCode));
}
};
回答by Pranay Rana
try this jquery code
试试这个 jquery 代码
$("body").keypress(function(e){
alert(e.which);
});
回答by K6t
You'll get the appropriate key code:
您将获得相应的密钥代码：
charfield.onkeydown=function(evt){
var keyCode = (evt.which?evt.which:(evt.keyCode?evt.keyCode:0))
alert(keyCode);
}
回答by natlee75
I can't off the top of my head think of a good situation in which to use the "on some event" method of a DOM element to deal with events on that element.
我无法想到使用 DOM 元素的“on some event”方法来处理该元素上的事件的好方法。
The best practice is to use addEventListener(or attachEventin older versions of Internet Explorer) like so:
最佳实践是像这样使用addEventListener（或attachEvent在旧版本的 Internet Explorer 中）：
charfield.addEventListener('keydown', function (e) { alert(e.keyCode); }, false);
If you want to account for attachEventas well:
如果您还想考虑attachEvent：
(function (useListen) {
if (useListen) {
charfield.addEventListener('keydown', alertKeyCode, false);
} else {
charfield.attachEvent('onkeydown', alertKeyCode);
}
})(charfield.addEventListener);
function alertKeyCode(e) {
alert(e.keyCode);
}
