03
JunAngular initializes automatically upon DOMContentLoaded event
or when the angular.js script is downloaded to the browser and the document.readyState
is set to complete
. At this point AngularJS looks for the ng-app directive which is the root of angular app compilation and tells about AngularJS part within DOM. When the ng-app directive is found then Angular will:
Load the module associated with the directive.
Create the application injector.
Compile the DOM starting from the ng-app root element.
This process is called auto-bootstrapping
.

<html> <body ng-app="myApp"> <div ng-controller="Ctrl"> Hello {{msg}}! </div> <script src="lib/angular.js"></script> <script> var app = angular.module('myApp', []); app.controller('Ctrl', function ($scope) { $scope.msg = 'World'; }); </script> </body> </html>
Manual Bootstrap Process
You can manually initialized your angular app by using angular.bootstrap()
function. This function takes the modules as parameters and should be called within angular.element(document).ready()
function. The angular.element(document).ready() function is fired when the DOM is ready for manipulation.
<html> <body> <div ng-controller="Ctrl"> Hello {{msg}}! </div> <script src="lib/angular.js"></script> <script> var app = angular.module('myApp', []); app.controller('Ctrl', function ($scope) { $scope.msg = 'World'; }); //manual bootstrap process angular.element(document).ready(function () { angular.bootstrap(document, ['myApp']); }); </script> </body> </html>
Note
You should not use the ng-app directive when manually bootstrapping your app.
You should not mix up the automatic and manual way of bootstrapping your app.
Define modules, controller, services etc. before manually bootstrapping your app as defined in above example.
What do you think?
I hope you will enjoy the AngularJS bootstrap process while developing your app with AngularJS. I would like to have feedback from my blog readers. Your valuable feedback, question, or comments about this article are always welcome.
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