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Do you have to watch the scope of an object in angularjs?


Asked by Rodney Hill on Nov 29, 2021 AngularJS



Fortunately, no. If you would watch for changes to every object in your $scope, then quickly a digest loop would take ages to evaluate and you would quickly run into performance issues. That is why the AngularJS team gave us two ways of declaring some $scope variable as being watched (read below).
In addition,
Scope in AngularJS. The $scope in an AngularJS is a built-in object, which contains application data and methods. You can create properties to a $scope object inside a controller function and assign a value or function to it. The $scope is glue between a controller and view (HTML). It transfers data from the controller to view and vice-versa.
Also, Angular uses $watch APIs to observe model changes on the scope. Angular registered watchers for each variable on scope to observe the change in its value. If the value, of variable on scope is changed then the view gets updated automatically. $watch APIs has following methods to observe model changes on the scope.
And,
When you create a data binding from somewhere in your view to a variable on the $scope object, AngularJS creates a "watch" internally. A watch means that AngularJS watches changes in the variable on the $scope object. The framework is "watching" the variable.
Thereof,
The AngularJS $scope functions $watch(), $digest() and $apply() are some of the central functions in AngularJS. Understanding $watch(), $digest() and $apply() is essential in order to understand AngularJS. When you create a data binding from somewhere in your view to a variable on the $scope object, AngularJS creates a "watch" internally.