如何编写在AngularJS中返回true / false的服务？

Question

I had been reading up on AngularJS Factory and Services and came across a lot of examples. 我一直在阅读AngularJS工厂和服务，并遇到了很多例子。 But I'm not understanding the logic behind them and can't get them to work either. 但是我不理解它们背后的逻辑，也无法使它们工作。

myApp.service('loginCheck', function(Facebook) {
this.loggedIn = false;
Facebook.login(function(response) {
    if (response.status == 'connected') {
        this.loggedIn = true;
    }
});
});

I need to get this service to return the loggedIn variable, if my idea of the concept is right. 如果我对概念的想法是正确的，那么我需要获得此服务以返回loggingIn变量。 Should I use a factory instead? 我应该改为使用工厂吗？ I need to store this variable all along, without making the call again every once I need it. 我需要一直存储此变量，而不必在需要时再次进行调用。 How can I do it. 我该怎么做。 I couldn't really understand the difference between factory and service. 我无法真正理解工厂和服务之间的区别。 I'm a beginner here. 我是这里的初学者。

if(loginCheck.loggedIn){
    console.log("logged in!");
}
else{
    console.log("not logged in :/")
}

Thank you. 谢谢。

Answer 1

You can do this, 你可以这样做，

app.service('MyUser', [function($scope) {
  this.loggedIn = false;
  return {
    getStatus: function() {
       //call fb api
       this.loggedIn = true;
       return this.loggedIn;
    }
  }
}]);

DEMO 演示

 var app = angular.module('app', []); app.controller('loginController',['$scope', 'MyUser',function($scope, MyUser) { $scope.isloggedin = MyUser.getStatus(); alert($scope.isloggedin); }]); app.service('MyUser', [function($scope) { this.loggedIn = false; return { getStatus: function() { this.loggedIn = true; return this.loggedIn; } } }]);

 <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title></title> </head> <body ng-app="app" ng-controller="loginController"> <script type="text/javascript" src="//ajax.googleapis.com/ajax/libs/angularjs/1.3.6/angular.js"></script> </body> </html>

Answer 2

Define a factory and passed to your controller as dependency. 定义一个工厂，并将其作为依赖项传递给您的控制器。

var myApp = angular.module('myApp', []);
myApp.factory('loginCheck', ["Facebook", function(Facebook) {
  var object = {
    loggedIn: false,
    loginFacebook: function() {
      // do facebook login here:
      //Facebook.login(function(response) {
      //  if (response.status == 'connected') {
          object.loggedIn = true;
      //  };
      }
    };

  object.loginFacebook();
  return object;
}]);

myApp.controller('myCtrl', ['loginCheck', '$scope', function(loginCheck, $scope) {
  $scope.loggedIn = loginCheck.loggedIn;
}]);

check this jsFiddle sample here . 在此处检查此jsFiddle示例。

I don't know about facebook authentication, but I think these links may help you : https://blog.brunoscopelliti.com/facebook-authentication-in-your-angularjs-web-app/ , https://developers.facebook.com/docs/javascript/howto/angularjs 我不知道关于Facebook的身份验证，但我认为这些链接可以帮助你： https://blog.brunoscopelliti.com/facebook-authentication-in-your-angularjs-web-app/ ， HTTPS：//developers.facebook .com / docs / javascript / howto / angularjs

To find different between service and factory look at this question or this link . 要找到服务和工厂之间的区别，请查看此问题或此链接。

如何编写在AngularJS中返回true / false的服务？

问题描述

2 个解决方案

解决方案1
3 2017-02-09 03:49:20

解决方案2
2 2017-02-09 04:12:51

如何编写在AngularJS中返回true / false的服务？

问题描述

2 个解决方案

解决方案1 3 2017-02-09 03:49:20

解决方案2 2 2017-02-09 04:12:51

解决方案1
3 2017-02-09 03:49:20

解决方案2
2 2017-02-09 04:12:51