Is there a way to ignore subscribers on a value change of the observable. Id like to change a value of an observable, but not execute it for the subscribers with knockout.js
To create an observable, assign the ko. observable function to the variable. A default value can be specified in the constructor of the call. Knockout then converts your variable into a function and tracks when the value changes, in order to notify the UI elements associated with the variable.
applyBindings do, The first parameter says what view model object you want to use with the declarative bindings it activates. Optionally, you can pass a second parameter to define which part of the document you want to search for data-bind attributes. For example, ko.
Knockout. js defines an important role when we want to detect and respond to changes on one object, we uses the observable. An observable is useful in various scenarios where we are displaying or editing multiple values and require repeated sections of the UI to appear and disappear as items are inserted and deleted.
Syntax. You just need to declare ViewModel property with function ko. observable() to make it Observable.
Normally this is not possible or advisable, as it potentially allows things to get out of sync in the dependency chains. Using the throttle extender is generally a good way to limit the amount of notifications that dependencies are receiving.
However, if you really want to do this, then one option would be to overwrite the notifySubscribers
function on an observable and have it check a flag.
Here is an extensions that adds this functionality to an observable:
ko.observable.fn.withPausing = function() { this.notifySubscribers = function() { if (!this.pauseNotifications) { ko.subscribable.fn.notifySubscribers.apply(this, arguments); } }; this.sneakyUpdate = function(newValue) { this.pauseNotifications = true; this(newValue); this.pauseNotifications = false; }; return this; };
You would add this to an observable like:
this.name = ko.observable("Bob").withPausing();
Then you would update it without notifications by doing:
this.name.sneakyUpdate("Ted");
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