Angular initializes automatically when you load the angular script into your page that contains an element
with ng:app
directive:
<!doctype html> <html ng:app> <head> <script src="angular.js"></script> </head> <body> I can add: {{ 1+2 }}. </body> </html>
From a high-level view, this is what happens during angular's automatic initialization process:
The browser loads the page, and then runs the angular script. Angular waits for the
DOMContentLoaded
(or 'Load') event to attempt to bootstrap.
Angular looks for the ng:app
directive. If found it then proceeds to compile the DOM element and its children.
Optionally the ng:app
may specify a module
to load before the compilation. For details on
how the compiler works, see Angular HTML Compiler.
The reason why ng:app
exists is because angular should not assume that the entire HTML
document should be processed just because the angular.js
script is included. In order to compile
only a part of the document set the ng:app
on the root element of this portion.
The angular script creates a single global variable angular
in the global namespace. All angular
APIs are bound to fields of this global object.