Angular Service已注入控制器，但它显示为空对象

Question

I have the following angular service.

angular.module('myApp')
.service('StatusService', function StatusService() {
    var statusService= {
        show: 'off',
        on: function() {
            this.show = 'on';
        },
        off: function() {
            this.show = 'off';
        }
    };

    return statusService;
});

Which is injected into a controller, and its on function is invoked, like this:

angular.module('myApp')
    .controller('aController', function (StatusService) {

    StatusService.on(); 
})

But I get the following error.

TypeError: Object #<Object> has no method 'on'

Answer 1

I think you're using a module.service() invocation with module.factory() implementation when declaring the service. either change the earlier to module.factory(StatusService) (which should really be called StatusServiceFactory ) OR change impl to add interface methods to StatusService itself ie:

function StatusService(){
this.show='off';
this.on = function(){};
}
module.service('statusService', StatusService);

Here's a demo of the above working: http://plnkr.co/edit/r07kPP85oQQKtJYMYOyK?p=preview

Answer 2

如果您在不同的地方声明了多个具有相同名称的服务，就会出现此问题，它会造成混乱并返回{}。