jQuery Keypress Arrow Keys

I'm attempting to capture arrow key presses in jQuery, but no events are being triggered.

$(function(){
$('html').keypress(function(e){
console.log(e);
});
});

This generates events for alphanumeric keys, but delete, arrow keys, etc generate no event.

What am I doing wrong to not be capturing those?

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小开 
$(document).keydown(function(e) {
console.log(e.keyCode);
});

Keypress events do detect arrow keys, but not in all browsers. So it's better to use keydown.

These are keycodes you should be getting in your console log:

  • left = 37
  • up = 38
  • right = 39
  • down = 40
小开
最佳答案

You should use .keydown() because .keypress() will ignore "Arrows", for catching the key type use e.which

Press the result screen to focus (bottom right on fiddle screen) and then press arrow keys to see it work.

Notes:

  1. .keypress() will never be fired with Shift, Esc, and Delete but .keydown() will.
  2. Actually .keypress() in some browser will be triggered by arrow keys but its not cross-browser so its more reliable to use .keydown().

More useful information

  1. You can use .which Or .keyCode of the event object - Some browsers won't support one of them but when using jQuery its safe to use the both since jQuery standardizes things. (I prefer .which never had a problem with).
  2. To detect a ctrl | alt | shift | META press with the actual captured key you should check the following properties of the event object - They will be set to TRUE if they were pressed:

  3. Finally - here are some useful key codes ( For a full list - keycode-cheatsheet ):

    • Enter: 13
    • Up: 38
    • Down: 40
    • Right: 39
    • Left: 37
    • Esc: 27
    • SpaceBar: 32
    • Ctrl: 17
    • Alt: 18
    • Shift: 16
小开

Please refer the link from JQuery

http://api.jquery.com/keypress/

It says

The keypress event is sent to an element when the browser registers keyboard input. This is similar to the keydown event, except that modifier and non-printing keys such as Shift, Esc, and delete trigger keydown events but not keypress events. Other differences between the two events may arise depending on platform and browser.

That means you can not use keypress in case of arrows.

小开

You can check wether an arrow key is pressed by:

$(document).keydown(function(e){
if (e.keyCode > 36 && e.keyCode < 41)
alert( "arrowkey pressed" );
});

jsfiddle demo

小开 
$(document).on( "keydown",  keyPressed);


function keyPressed (e){
e = e || window.e;
var newchar = e.which || e.keyCode;
alert(newchar)
}
小开 
left = 37,up = 38, right = 39,down = 40


$(document).keydown(function(e) {
switch(e.which) {
case 37:
$( "#prev" ).click();
break;


case 38:
$( "#prev" ).click();
break;


case 39:
$( "#next" ).click();
break;


case 40:
$( "#next" ).click();
break;


default: return;
}
e.preventDefault();

});


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