在处理之前用jQuery拦截所有按键 [英] Intercepting all key presses with jQuery before they are processed

问题描述

我有一个网页，我需要拦截所有按键，然后才能调度到dom中有焦点的任何元素。当用户键入类似 ~goto：/index.html：（实际上它将来自条形码扫描仪）时，我需要在<$ c后捕获按键$ c>〜在我到达第二个：时解析它们。我设法用 $（文件）.keypress（）获得了如下内容：

I have a web page and I need to intercept all keypresses before they get dispatched to whatever element in the dom has the focus. When the user types something like ~goto:/index.html: (which in fact will come from a barcode scanner) I need to capture the key presses after the ~ to parse them once I get to the second :. I've managed to get something with the $(document).keypress() as follows:

$(document).ready(function() {
  $(document).keypress(function(e) {
    // do the processing here and 
    // return false when ignoring keystrokes
  });
});

问题是我在进入焦点元素后得到了按键。无论如何得到它以便我实际上可以拒绝它？

The problem is that I get the keypress after it has gone to the focussed element. Anyway to get it before so that I can in fact reject it?

推荐答案

你可能会有更好的运气 keydown 它应该在事件发生前触发

You will probably have better luck with keydown it should fire before the event

也这样做

$(document).keydown(function(e) {
    e.preventDefault();
});

调用preventDefault将停止按键的正常进程。实际上，您可以使用按键，只需使用preventDefault来完成拦截需求。

calling preventDefault will stop normal process of the key press. Actually, you may be able to stay with keypress and just use the preventDefault to finish your interception needs.

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