How to detect pressed keys on the click of AngularJS

All we need is an easy explanation of the problem, so here it is.

I’m using angularjs on a web application that I need to figure out how can I detect is keys like ctrl, shift or alt are pressed when I click somewhere.

For example, with jQuery I can do that by accessing the Click function arguments.

Is there some out-of-the-box way to obtain that information on angular?

How to solve :

I know you bored from this bug, So we are here to help you! Take a deep breath and look at the explanation of your problem. We have many solutions to this problem, But we recommend you to use the first method because it is tested & true method that will 100% work for you.

Method 1

In your html

<button ng-click="doSomething($event)"></button>

In your js

$scope.doSomething = function($event)
{
if ($event.altKey){}
if ($event.ctrlKey){}
if ($event.shiftKey){}
}

Method 2

Take a look at this beautiful Stuff regarding AngularJS key handling

So key code for Ctrl, shift, alt will be

Ctrl – 17
Alt – 18
Shift – 16

Working Demo

HTML

<!DOCTYPE html>
<html>
<head>
  <script src="angular.js"></script>
  <script src="script.js"></script>
</head>

<body ng-app="mainModule">
  <div ng-controller="mainController">
    <label>Type something:
      <input type="text"
             ng-keydown="onKeyDown($event)"
             ng-keyup="onKeyUp($event)"
             ng-keypress="onKeyPress($event)" />
    </label><br />
    <strong>KEY DOWN RESULT:</strong> {{onKeyDownResult}}<br />
    <strong>KEY UP RESULT:</strong> {{onKeyUpResult}}<br />
    <strong>KEY PRESS RESULT:</strong> {{onKeyPressResult}}
  </div>
</body>
</html>

SCRIPT

angular.module("mainModule", [])
  .controller("mainController", function ($scope)
  {
    // Initialization
    $scope.onKeyDownResult = "";
    $scope.onKeyUpResult = "";
    $scope.onKeyPressResult = "";

    // Utility functions

    var getKeyboardEventResult = function (keyEvent, keyEventDesc)
    {
      return keyEventDesc + " (keyCode: " + (window.event ? keyEvent.keyCode : keyEvent.which) + ")";
    };

    // Event handlers
    $scope.onKeyDown = function ($event) {
      $scope.onKeyDownResult = getKeyboardEventResult($event, "Key down");
    };

    $scope.onKeyUp = function ($event) {
      $scope.onKeyUpResult = getKeyboardEventResult($event, "Key up");
    };

    $scope.onKeyPress = function ($event) {
      $scope.onKeyPressResult = getKeyboardEventResult($event, "Key press");
    };
  });

Method 3

There is no “automated” way using pure JS, but it’s relatively simple to track modifier keys’ state in global variables. E.g.

window.ctrlDown = false;

document.addEventListener('keydown', function(evt) {
  var e = window.event || evt;
  var key = e.which || e.keyCode;
  if(17 == key) {
    window.ctrlDown = true;
  }
}, false);

document.addEventListener('keyup', function(evt) {
  var e = window.event || evt;
  var key = e.which || e.keyCode;
  if(17 == key) {
    window.ctrlDown = false;
  }
}, false);

Method 4

If you are trying to capture a key combination, such as Ctrl-Enter, you can look at the window object

For example to find Ctrl-Enter use

if(window.event.keyCode == 13 && window.event.ctrlKey == true)

Method 5

Since I’m not sure what each browser provides, I would do it this way:

shiftPressed = event.shiftKey || (event.keyCode === 16);

On Chorme for example I can’t see any event.keyCode on the click event:

altKey: false
bubbles: true
button: 0
buttons: 0
cancelBubble: false
cancelable: true
clientX: 753
clientY: 193
ctrlKey: false
currentTarget: null
defaultPrevented: false
detail: 1
eventPhase: 0
fromElement: null
isDefaultPrevented: ()
isImmediatePropagationStopped: ()
isTrusted: true
isTrusted: true
layerX: 4
layerY: -15
metaKey: false
movementX: 0
movementY: 0
offsetX: 4
offsetY: -15
pageX: 1381
pageY: 193
path: Array[16]
relatedTarget: null
returnValue: true
screenX: 753
screenY: 278
shiftKey: true
srcElement: span.glyphicon.glyphicon-plus
stopImmediatePropagation: ()
target: span.glyphicon.glyphicon-plus
timeStamp: 1445613423528
toElement: span.glyphicon.glyphicon-plus
type: "click"
view: Window
webkitMovementX: 0
webkitMovementY: 0
which: 1
x: 753
y: 193

Note: Use and implement method 1 because this method fully tested our system.
Thank you 🙂

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0

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