JavaScript KeyCode与CharCode [英] JavaScript KeyCode vs CharCode

问题描述

问题：

• 将HTML输入中允许的字符限制为仅限az AZ。


• 对于业务需求，这需要在KeyPress上完成，以便角色根本不允许出现在输入中。


• Tab，enter，arrows，backspace，shift都是允许的。用户必须能够自由地移入和移出文本框，删除字符等等。

这是我的起点代码...

This is the starting point of my code...

var keyCode = (e.keyCode ? e.keyCode : e.which);

但是我在 keyCode 中获得的每个值都与不对应我在网上看到的任何字符图表。例如，字符h给我一个返回码104.

However every value that I get in keyCode doesnt correspond to any of the character charts I have seen on the web. For example the character "h" gives me a return code of 104.

KeyCode与CharCode不同吗？哪个代码包含控制字符？我需要转换吗？

Is KeyCode different to CharCode? Which code contains the control characters? Do I need to convert?

如何将输入限制为az AZ并允许我在JavaScript中需要的键？

How can I restrict the input to a-z A-Z and allow the keys I need in JavaScript?

推荐答案

您可以在上找到所有问题的答案。以下页面。

...但总结如下：

• 您可以可靠地获取角色信息（而不是密钥代码信息）的唯一事件是 keypress 事件。


• In keypress 事件，除IE< = 8之外的所有浏览器都将字符代码存储在事件的中属性中。大多数但不是所有这些浏览器还将字符代码存储在 charCode 属性中。


• 在 keypress中 event，IE< = 8将字符代码存储在 keyCode 属性中。

• The only event from which you can reliably obtain character information (as opposed to key code information) is the keypress event.
• In the keypress event, all browsers except IE <= 8 store the character code in the event's which property. Most but not all of these browsers also store the character code in the charCode property.
• In the keypress event, IE <= 8 stores the character code in the keyCode property.

这意味着要获得与按键相对应的字符代码，假设按键事件对象存储在名为 e ：

This means to get the character code corresponding to the keypress, the following will work everywhere, assuming a keypress event object is stored in a variable called e:

var charCode = (typeof e.which == "number") ? e.which : e.keyCode

这通常会返回一个存在的字符代码，否则为0 。在某些情况下，如果不这样做，您将获得非零值：

This will generally return you a character code where one exists and 0 otherwise. There are a few cases where you'll get a non-zero value when you shouldn't:

• 在Opera< 10.50为键插入，删除，主页和结束


• In最新版本的Konqueror用于非字符键。

• In Opera < 10.50 for keys Insert, Delete, Home and End
• In recent versions of Konqueror for non-character keys.

第一个问题的解决方法有点涉及，需要使用 keydown 事件。

The workaround for the first problem is a little involved and requires using the keydown event as well.

这篇关于JavaScript KeyCode与CharCode的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！