Unbinding $watch in angularjs after called

you can just do it the same way you already do, call the "deregistration" inside your function:

var unbind = $scope.$watch("tag", function () {    // ...    unbind();});

javascript angularjs frameworks

Because tag is an expression, you can use one-time binding to unbind once the value was received:

$scope.$watch("::tag", function () {});

angular.module('app', []).controller('example', function($scope, $interval) {  $scope.tag = undefined  $scope.$watch('::tag', function(tag) {    $scope.tagAsSeen = tag  })  $interval(function() {    $scope.tag = angular.isDefined($scope.tag) ? $scope.tag + 1 : 1  }, 1000)})angular.bootstrap(document, ['app'])

<html><head><script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.4.0/angular.min.js"></script>  <meta charset="utf-8">  <meta name="viewport" content="width=device-width">  <title>JS Bin</title></head><body ng-controller="example">Tag: {{tag}}<br>Watch once result: {{tagAsSeen}}</body></html>

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