Why use angular's $log instead of console.log?
AngularjsLoggingAngularjs Problem Overview
I understand it is a best practice in angular to use $log
instead of console.log
.
However, I can't find good documentation explaining the reasons. Why should a developer use $log
?
Angularjs Solutions
Solution 1 - Angularjs
$log
first checks if the browser supports console.log
(IE 8, for example, doesn't). This prevents errors being displayed on IE 8. Note: this doesn't mean it will log anything on IE 8, it simply means it won't throw the error.
Next to that, it also allows you to decorate and mock $log
for extending and testing purposes, if you are so inclined. You could for example decorate it to log to an array for IE 8 support.
A bonus feature: if you pass it a JavaScript Error
instance, it will attempt to format it nicely. This can be found out by reading the source code.
EDIT: "It is not that IE 8 doesn't support console.log. It just doesn't create the console object until the dev tools are opened." See comments below for more details.
Solution 2 - Angularjs
Just to complete @Steve's answer (which is correct), $log
also has the advantage of being turned off. Using this code you can disable the logging from $log
:
app.config(function($logProvider) {
$logProvider.debugEnabled(true);
});
This is very handy if you want to disable all logs at once, rather than delete them line by line manually.