使用 jQuery 监听 keydown 事件

Using jQuery to listen to keydown event(使用 jQuery 监听 keydown 事件)

问题描述

我想检测何时按下回车键，在 HTML 上动态注入.

I want to detect when the enter key is pressed, on HTML that will be injected dynamically.

要简单地检测何时按下回车键，我可以这样做:

To simply detect when the enter key is pressed, I can do:

$('#textfield').keydown(function (e){
    if(e.keyCode == 13){
        console.log('Enter was pressed');
    }
})

此代码适用于 on()，但我担心它效率低下，因为 jQuery 会在每次按下键时进行检查.这有什么低效的地方吗?

This code works for on(), but I am worried it is inefficient since jQuery will check every time a key is pressed. Is there anything inefficient about this?

$('body').on('keydown','#textfield', function(event) {
  if (event.keyCode == 13) {
    console.log('Enter was pressed');
  }
}

推荐答案

如果你想捕捉页面任意位置的按键 -

If you want to capture the keypress anywhere on the page -

$(document).keypress(function(e) {
  if(e.which == 13) {
    // enter pressed
  }
});

不用担心它会检查每个按键，它确实不会给浏览器带来任何显着负载.

Don't worry about the fact this checks for every keypress, it really isn't putting any significant load on the browser.

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