Home » Angularjs » How to use a keypress event in AngularJS?

How to use a keypress event in AngularJS?

Posted by: admin November 2, 2017 Leave a comment

Questions:

I want to catch the enter key press event on the textbox below. To make it more clear I am using a ng-repeat to populate the tbody. Here is the HTML:

<td><input type="number" id="closeqty{{$index}}" class="pagination-right closefield" 
    data-ng-model="closeqtymodel" data-ng-change="change($index)" required placeholder="{{item.closeMeasure}}" /></td>

This is my module:

angular.module('components', ['ngResource']);

I am using a resource to populate the table and my controller code is:

function Ajaxy($scope, $resource) {
//controller which has resource to populate the table 
}
Answers:

You need to add a directive, like this:

Javascript:

app.directive('myEnter', function () {
    return function (scope, element, attrs) {
        element.bind("keydown keypress", function (event) {
            if(event.which === 13) {
                scope.$apply(function (){
                    scope.$eval(attrs.myEnter);
                });

                event.preventDefault();
            }
        });
    };
});

HTML:

<div ng-app="" ng-controller="MainCtrl">
    <input type="text" my-enter="doSomething()">    
</div>

Questions:
Answers:

An alternative is to use standard directive ng-keypress="myFunct($event)"

Then in your controller you can have:

...

$scope.myFunct = function(keyEvent) {
  if (keyEvent.which === 13)
    alert('I am an alert');
}

...

Questions:
Answers:

My simplest approach using just angular build-in directive:

ng-keypress, ng-keydown or ng-keyup.

Usually, we want add keyboard support for something that already handled by ng-click.

for instance:

<a ng-click="action()">action</a>

Now, let’s add keyboard support.

trigger by enter key:

<a ng-click="action()" 
   ng-keydown="$event.keyCode === 13 && action()">action</a>

by space key:

<a ng-click="action()" 
   ng-keydown="$event.keyCode === 32 && action()">action</a>

by space or enter key:

<a ng-click="action()" 
   ng-keydown="($event.keyCode === 13 || $event.keyCode === 32) && action()">action</a>

if you are in modern browser

<a ng-click="action()" 
   ng-keydown="[13, 32].includes($event.keyCode) && action()">action</a>

More about keyCode:
keyCode is deprecated but well supported API, you could use $evevt.key in supported browser instead.
See more in https://developer.mozilla.org/en-US/docs/Web/API/KeyboardEvent/key

Questions:
Answers:

Another simple alternative:

<input ng-model="edItem" type="text" 
    ng-keypress="($event.which === 13)?foo(edItem):0"/>

And the ng-ui alternative:

<input ng-model="edItem" type="text" ui-keypress="{'enter':'foo(edItem)'}"/>

Questions:
Answers:

Here is what I figured out when I was building an app with a similar requirement,
it doesn’t require writing a directive and it’s relatively simple to tell what it does:

<input type="text" ng-keypress="($event.charCode==13)?myFunction():return" placeholder="Will Submit on Enter">

Questions:
Answers:

You can use ng-keydown
=”myFunction($event)” as attribute.

<input ng-keydown="myFunction($event)" type="number">

myFunction(event) {
    if(event.keyCode == 13) {   // '13' is the key code for enter
        // do what you want to do when 'enter' is pressed :)
    }
}

Questions:
Answers:

Trying

ng-keypress="console.log($event)"
ng-keypress="alert(123)"

did nothing for me.

Strangley the sample at https://docs.angularjs.org/api/ng/directive/ngKeypress, which does ng-keypress=”count = count + 1″, works.

I found an alternate solution, which has pressing Enter invoke the button’s ng-click.

<input ng-model="..." onkeypress="if (event.which==13) document.getElementById('button').click()"/>
<button id="button" ng-click="doSomething()">Done</button>

Questions:
Answers:

html

<textarea id="messageTxt" 
    rows="5" 
    placeholder="Escriba su mensaje" 
    ng-keypress="keyPressed($event)" 
    ng-model="smsData.mensaje">
</textarea>

controller.js

$scope.keyPressed = function (keyEvent) {
    if (keyEvent.keyCode == 13) {
        alert('presiono enter');
        console.log('presiono enter');
    }
};

Questions:
Answers:

You can also apply it to a controller on a parent element. This example can be used to highlight a row in a table by pressing up/down arrow keys.

app.controller('tableCtrl', [ '$scope', '$element', function($scope, $element) {
  $scope.index = 0; // row index
  $scope.data = []; // array of items
  $scope.keypress = function(offset) {
    console.log('keypress', offset);
    var i = $scope.index + offset;
    if (i < 0) { i = $scope.data.length - 1; }
    if (i >= $scope.data.length) { i = 0; }
  };
  $element.bind("keydown keypress", function (event) {
    console.log('keypress', event, event.which);
    if(event.which === 38) { // up
      $scope.keypress(-1);
    } else if (event.which === 40) { // down
      $scope.keypress(1);
    } else {
      return;
    }
    event.preventDefault();
  });
}]);


<table class="table table-striped" ng-controller="tableCtrl">
<thead>
    <tr>
        <th ng-repeat="(key, value) in data[0]">{{key}}</th>
    </tr>
</thead>
<tbody>
    <tr ng-repeat="row in data track by $index" ng-click="draw($index)" ng-class="$index == index ? 'info' : ''">
        <td ng-repeat="(key, value) in row">{{value}}</td>
    </tr>
</tbody>
</table>

Questions:
Answers:

This is an extension on the answer from EpokK.

I had the same problem of having to call a scope function when enter is pushed on an input field. However I also wanted to pass the value of the input field to the function specified. This is my solution:

app.directive('ltaEnter', function () {
return function (scope, element, attrs) {
    element.bind("keydown keypress", function (event) {
        if(event.which === 13) {
          // Create closure with proper command
          var fn = function(command) {
            var cmd = command;
            return function() {
              scope.$eval(cmd);
            };
          }(attrs.ltaEnter.replace('()', '("'+ event.target.value +'")' ));

          // Apply function
          scope.$apply(fn);

          event.preventDefault();
        }
    });
};

});

The use in HTML is as follows:

<input type="text" name="itemname" lta-enter="add()" placeholder="Add item"/>

Kudos to EpokK for his answer.

Questions:
Answers:

What about this?:

<form ng-submit="chat.sendMessage()">
    <input type="text" />
    <button type="submit">
</form>

Now when you push enter key after write something in your input, the form know how to handle it.

Questions:
Answers:

Some example of code that I did for my project.
Basically you add tags to your entity.
Imagine you have input text, on entering Tag name you get drop-down menu with preloaded tags to choose from, you navigate with arrows and select with Enter:

HTML + AngularJS v1.2.0-rc.3

    <div>
        <form ng-submit="addTag(newTag)">
            <input id="newTag" ng-model="newTag" type="text" class="form-control" placeholder="Enter new tag"
                   style="padding-left: 10px; width: 700px; height: 33px; margin-top: 10px; margin-bottom: 3px;" autofocus
                   data-toggle="dropdown"
                   ng-change="preloadTags()"
                   ng-keydown="navigateTags($event)">
            <div ng-show="preloadedTags.length > 0">
                <nav class="dropdown">
                    <div class="dropdown-menu preloadedTagPanel">
                        <div ng-repeat="preloadedTag in preloadedTags"
                             class="preloadedTagItemPanel"
                             ng-class="preloadedTag.activeTag ? 'preloadedTagItemPanelActive' : '' "
                             ng-click="selectTag(preloadedTag)"
                             tabindex="{{ $index }}">
                            <a class="preloadedTagItem"
                               ng-class="preloadedTag.activeTag ? 'preloadedTagItemActive' : '' "
                               ng-click="selectTag(preloadedTag)">{{ preloadedTag.label }}</a>
                        </div>
                    </div>
                </nav>
            </div>
        </form>
    </div>

Controller.js

$scope.preloadTags = function () {
    var newTag = $scope.newTag;
    if (newTag && newTag.trim()) {
        newTag = newTag.trim().toLowerCase();

        $http(
            {
                method: 'GET',
                url: 'api/tag/gettags',
                dataType: 'json',
                contentType: 'application/json',
                mimeType: 'application/json',
                params: {'term': newTag}
            }
        )
            .success(function (result) {
                $scope.preloadedTags = result;
                $scope.preloadedTagsIndex = -1;
            }
        )
            .error(function (data, status, headers, config) {
            }
        );
    } else {
        $scope.preloadedTags = {};
        $scope.preloadedTagsIndex = -1;
    }
};

function checkIndex(index) {
    if (index > $scope.preloadedTags.length - 1) {
        return 0;
    }
    if (index < 0) {
        return $scope.preloadedTags.length - 1;
    }
    return index;
}

function removeAllActiveTags() {
    for (var x = 0; x < $scope.preloadedTags.length; x++) {
        if ($scope.preloadedTags[x].activeTag) {
            $scope.preloadedTags[x].activeTag = false;
        }
    }
}

$scope.navigateTags = function ($event) {
    if (!$scope.newTag || $scope.preloadedTags.length == 0) {
        return;
    }
    if ($event.keyCode == 40) {  // down
        removeAllActiveTags();
        $scope.preloadedTagsIndex = checkIndex($scope.preloadedTagsIndex + 1);
        $scope.preloadedTags[$scope.preloadedTagsIndex].activeTag = true;
    } else if ($event.keyCode == 38) {  // up
        removeAllActiveTags();
        $scope.preloadedTagsIndex = checkIndex($scope.preloadedTagsIndex - 1);
        $scope.preloadedTags[$scope.preloadedTagsIndex].activeTag = true;
    } else if ($event.keyCode == 13) {  // enter
        removeAllActiveTags();
        $scope.selectTag($scope.preloadedTags[$scope.preloadedTagsIndex]);
    }
};

$scope.selectTag = function (preloadedTag) {
    $scope.addTag(preloadedTag.label);
};

CSS + Bootstrap v2.3.2

.preloadedTagPanel {
    background-color: #FFFFFF;
    display: block;
    min-width: 250px;
    max-width: 700px;
    border: 1px solid #666666;
    padding-top: 0;
    border-radius: 0;
}

.preloadedTagItemPanel {
    background-color: #FFFFFF;
    border-bottom: 1px solid #666666;
    cursor: pointer;
}

.preloadedTagItemPanel:hover {
    background-color: #666666;
}

.preloadedTagItemPanelActive {
    background-color: #666666;
}

.preloadedTagItem {
    display: inline-block;
    text-decoration: none;
    margin-left: 5px;
    margin-right: 5px;
    padding-top: 5px;
    padding-bottom: 5px;
    padding-left: 20px;
    padding-right: 10px;
    color: #666666 !important;
    font-size: 11px;
}

.preloadedTagItem:hover {
    background-color: #666666;
}

.preloadedTagItemActive {
    background-color: #666666;
    color: #FFFFFF !important;
}

.dropdown .preloadedTagItemPanel:last-child {
    border-bottom: 0;
}

Questions:
Answers:

I’m a bit late .. but i found a simpler solution using auto-focus .. This could be useful for buttons or other when popping a dialog :

<button auto-focus ng-click="func()">ok</button>

That should be fine if you want to press the button onSpace or Enter clicks .

Questions:
Answers:

here’s my directive:

mainApp.directive('number', function () {
    return {
        link: function (scope, el, attr) {
            el.bind("keydown keypress", function (event) {
                //ignore all characters that are not numbers, except backspace, delete, left arrow and right arrow
                if ((event.keyCode < 48 || event.keyCode > 57) && event.keyCode != 8 && event.keyCode != 46 && event.keyCode != 37 && event.keyCode != 39) {
                    event.preventDefault();
                }
            });
        }
    };
});

usage:

<input number />

Questions:
Answers:

you can use ng-keydown , ng-keyup , ng-press such as this .

to triger a function :

   <input type="text" ng-keypress="function()"/>

or if you have one condion such as when he press escape (27 is the key
code for escape)

 <form ng-keydown=" event.which=== 27?cancelSplit():0">
....
</form>

Questions:
Answers:

I think using document.bind is a bit more elegant

constructor($scope, $document) {
  var that = this;
  $document.bind("keydown", function(event) {
    $scope.$apply(function(){
      that.handleKeyDown(event);
    });
  });
}

To get document to the controller constructor:

controller: ['$scope', '$document', MyCtrl]