Otherwise on StateProvider

Using angular-ui-router, How can I use the otherwise method on $stateProvider or how can I use it at all ?

You can't use only $stateProvider.

You need to inject $urlRouterProvider and create a code similar to:

$urlRouterProvider.otherwise('/otherwise');

The /otherwise url must be defined on a state as usual:

 $stateProvider
    .state("otherwise", { url : '/otherwise'...})

See this link where ksperling explains

You can with $stateProvider using the catch all syntax ("*path"). You just need to add a state config at the bottom of your list like the following one:

$stateProvider.state("otherwise", {
    url: "*path",
    templateUrl: "views/error-not-found.html"
});

All the options are explained in https://github.com/angular-ui/ui-router/wiki/URL-Routing#regex-parameters.

The nice thing of this option, as opposed to $urlRouterProvider.otherwise(...), is that you 're not forced to a location change.

You can also manually inject $state into the otherwise function, which you can then navigate to a non-url state. This has the benefit of the browser not changing the addressbar, which is helpful for handling going back to a previous page.

    $urlRouterProvider.otherwise(function ($injector, $location) {
        var $state = $injector.get('$state');
        
        $state.go('defaultLayout.error', {
            title: "Page not found",
            message: 'Could not find a state associated with url "'+$location.$$url+'"'
        });
    });

I just want to chime in on the great answers that are already provided. The latest version of @uirouter/angularjs marked the class UrlRouterProvider as deprecated. They now recommend using UrlService instead. You can achieve the same result with the following modification:

$urlService.rules.otherwise('/defaultState');

Additional methods: https://ui-router.github.io/ng1/docs/1.0.16/interfaces/url.urlrulesapi.html

Ok, the silly moment when you realize that the question you asked is already answered in the first lines of the sample code! Just take a look at the sample code.

       angular.module('sample', ['ui.compat'])
      .config(
        [        '$stateProvider', '$routeProvider', '$urlRouterProvider',
        function ($stateProvider,   $routeProvider,   $urlRouterProvider) {
          $urlRouterProvider
            .when('/c?id', '/contacts/:id')
            .otherwise('/'); // <-- This is what I was looking for ! 


          ....

Take a look here.

The accepted answer references angular-route asks about ui-router. The accepted answer uses the "monolithic" $routeProvider, which requires the ngRoute module (whereas ui-router needs the ui.router module)

The highest-rated answer uses $stateProvider instead, and says something like .state("otherwise", { url : '/otherwise'... }), but I can't find any mention of "otherwise" in the documentation it links. However, I see that $stateProvider is mentioned in this answer where it says:

> You can't use only $stateProvider. You need to inject $urlRouterProvider

That's where my answer might help you. For me, it was sufficient to use $urlRouterProvider just like this:

 my_module
   .config([
	, '$urlRouterProvider'
	, function(
		, $urlRouterProvider){
			//When the url is empty; i.e. what I consider to be "the default"
			//Then send the user to whatever state is served at the URL '/starting' 
			//(It could say '/default' or any other path you want)
			$urlRouterProvider
					.when('', '/starting');
					//...
	}]);
			

My suggestion is consistent with the ui-router documentation, (this specific revision), where it includes a similar use of the .when(...) method (the first call to the function):

app.config(function($urlRouterProvider){
  // when there is an empty route, redirect to /index   
  $urlRouterProvider.when('', '/index');

  // You can also use regex for the match parameter
  $urlRouterProvider.when(/aspx/i, '/index');
})