How to pass an object into a state using UI-router?

There are two parts of this problem

1) using a parameter that would not alter an url (using params property):

$stateProvider
    .state('login', {
        params: [
            'toStateName',
            'toParamsJson'
        ],
        templateUrl: 'partials/login/Login.html'
    })

2) passing an object as parameter: Well, there is no direct way how to do it now, as every parameter is converted to string (EDIT: since 0.2.13, this is no longer true - you can use objects directly), but you can workaround it by creating the string on your own

toParamsJson = JSON.stringify(toStateParams);

and in target controller deserialize the object again

originalParams = JSON.parse($stateParams.toParamsJson);

In version 0.2.13, You should be able to pass objects into $state.go,

$state.go('myState', {myParam: {some: 'thing'}})

$stateProvider.state('myState', {
                url: '/myState/{myParam:json}',
                params: {myParam: null}, ...

and then access the parameter in your controller.

$stateParams.myParam //should be {some: 'thing'}

myParam will not show up in the URL.

Source:

See the comment by christopherthielen https://github.com/angular-ui/ui-router/issues/983, reproduced here for convenience:

christopherthielen: Yes, this should be working now in 0.2.13.

.state('foo', { url: '/foo/:param1?param2', params: { param3: null } // null is the default value });

$state.go('foo', { param1: 'bar', param2: 'baz', param3: { id: 35, name: 'what' } });

$stateParams in 'foo' is now { param1: 'bar', param2: 'baz', param3: { id: 35, name: 'what' } }

url is /foo/bar?param2=baz.