如果你使用的是普通Javascript，请注意keyCode现在已弃用并将被删除:

该特性已从Web标准中删除。尽管一些浏览器可能仍然支持它，但它正在被抛弃的过程中。尽量避免使用它，并更新现有的代码;请参阅本页底部的兼容性表，以指导您的决定。请注意，此功能可能在任何时候停止工作

https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/keyCode

相反，根据你想要的行为使用:.key或.code: https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/code https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/key

两者都是在现代浏览器上实现的。

在Firefox中，keyCode属性对onkeypress事件不起作用(只会返回0)。对于跨浏览器的解决方案，将which属性与keyCode一起使用，例如:

var x = event.which || event.keyCode;  // Use either which or keyCode, depending on browser support

jQuery规范化事件。这取决于是否事件。这事件。keyCode或事件。charCode是浏览器支持的:

// Add which for key events
if ( event.which == null && (event.charCode != null || event.keyCode != null) ) {
   event.which = event.charCode != null ? event.charCode : event.keyCode;
}

.which的另一个好处是jQuery对鼠标点击也这样做:

// Add which for click: 1 === left; 2 === middle; 3 === right
// Note: button is not normalized, so don't use it
if ( !event.which && event.button !== undefined ) {
    event.which = (event.button & 1 ? 1 : ( event.button & 2 ? 3 : ( event.button & 4 ? 2 : 0 ) ));
}

看看这个:https://developer.mozilla.org/en-US/docs/Web/API/event.keyCode

In a keypress event, the Unicode value of the key pressed is stored in either the keyCode or charCode property, never both. If the key pressed generates a character (e.g. 'a'), charCode is set to the code of that character, respecting the letter case. (i.e. charCode takes into account whether the shift key is held down). Otherwise, the code of the pressed key is stored in keyCode. keyCode is always set in the keydown and keyup events. In these cases, charCode is never set. To get the code of the key regardless of whether it was stored in keyCode or charCode, query the which property. Characters entered through an IME do not register through keyCode or charCode.

一个健壮的Javascript库，用于捕获键盘输入和输入的组合键。它没有依赖关系。

http://jaywcjlove.github.io/hotkeys/

hotkeys('ctrl+a,ctrl+b,r,f', function(event,handler){
    switch(handler.key){
        case "ctrl+a":alert('you pressed ctrl+a!');break;
        case "ctrl+b":alert('you pressed ctrl+b!');break;
        case "r":alert('you pressed r!');break;
        case "f":alert('you pressed f!');break;
    }
});

热键支持以下修饰符:` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` ` `。

以下特殊键可用于快捷键:退格键、tab键、清除键、enter键、return键、esc键、escape键、空格键、上、下、左、右、home键、end键、pageup键、pagedown键、del键、delete键以及f1到f19键。

Note: The answer below was written in 2010. Here many years later, both keyCode and which are deprecated in favor of key (for the logical key) and code (for the physical placement of the key). But note that IE doesn't support code, and its support for key is based on an older version of the spec so isn't quite correct. As I write this, the current Edge based on EdgeHTML and Chakra doesn't support code either, but Microsoft is rolling out its Blink- and V8- based replacement for Edge, which presumably does/will.

有些浏览器使用keyCode，有些使用which。

如果你使用的是jQuery，你可以可靠地使用它，因为jQuery是标准化的;更多的在这里。

如果你没有使用jQuery，你可以这样做:

var key = 'which' in e ? e.which : e.keyCode;

或者:

var key = e.which || e.keyCode || 0;

…它处理e.which可能为0的可能性(通过使用JavaScript功能强大的||操作符，在末尾恢复0)。