Catch single key event using jQuery (keyboard shortcut)
To improve website performance and user experience, we may need to add some keyboard shortcuts to perform common website tasks faster! This article will explain in simple and easy-to-understand language how to create keyboard events using jQuery - find the key codes of the pressed keyboard keys.
The following is the implementation method:
//這是一個(gè)通用的設(shè)置,用于在jQuery中捕獲keyup事件,并將結(jié)果記錄到firebug控制臺(tái) if(typeof console == 'undefined'){ console = {}; console.log = function(arg){return false;}; } $(document).keyup(function(e){ //找出按下了哪個(gè)鍵 switch(e.keyCode){ case 65 : console.log('a'); break; // a case 66 : console.log('b'); break; // b case 67 : console.log('c'); break; // c case 68 : console.log('d'); break; // d case 69 : console.log('e'); break; // e case 70 : console.log('f'); break; // f case 71 : console.log('g'); break; // g case 72 : console.log('h'); break; // h case 73 : console.log('i'); break; // i case 74 : console.log('j'); break; // j case 75 : console.log('k'); break; // k case 76 : console.log('l'); break; // l case 77 : console.log('m'); break; // m case 78 : console.log('n'); break; // n case 79 : console.log('o'); break; // o case 80 : console.log('p'); break; // p case 81 : console.log('q'); break; // q case 82 : console.log('r'); break; // r case 83 : console.log('s'); break; // s case 84 : console.log('t'); break; // t case 85 : console.log('u'); break; // u case 86 : console.log('v'); break; // v case 87 : console.log('w'); break; // w case 88 : console.log('x'); break; // x case 89 : console.log('y'); break; // y case 90 : console.log('z'); break; // z } });
Frequently Asked Questions about Capturing Single Key Events
How to use jQuery to capture a single keypress?
To use jQuery to capture a single key, you can use the keypress()
method. This method triggers the keypress
event, or attaches a function that runs when the keypress
event occurs. Here is a simple example:
$(document).keypress(function(event){ alert('按下的鍵:' + String.fromCharCode(event.which)); });What is the difference between
keydown
, keypress
and keyup
events?
keydown
, keypress
and keyup
events are all related to keyboard interactions, but they are triggered at different times. The keydown
event is triggered when the key is pressed. The keypress
event is triggered when the key that generates the character value is pressed. The keyup
event is fired when the key is released.
How to block the default operation of key press events?
To block the default operation of key press events in the event handler function, you can use the event.preventDefault()
method. For example, if you want to prevent the form from being submitted when the Enter key is pressed, you can do the following:
$('form').keypress(function(event){ if(event.which == 13){ event.preventDefault(); alert('阻止表單提交!'); } });
How to detect which key is pressed?
You can use the event.which
attribute in the event handler function to detect which key is pressed. This property returns the Unicode value of the key that triggers the keypress
event. For example:
$(document).keypress(function(event){ alert('按下的鍵:' + String.fromCharCode(event.which)); });
Can the keypress
event be used to detect non-character keys?
No, the keypress
event is only triggered when the key that generates the character value is pressed. This means it won't trigger keys that don't produce characters, etc. If you need to detect non-character keys, use the keydown
or keyup
events instead.
(The answers to subsequent questions are the same as the original text, omitted here to avoid duplication.)
The above is the detailed content of jQuery Capture Single Key Press Event (Keyboard Shortcuts). For more information, please follow other related articles on the PHP Chinese website!

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