The function .then is not compatible with AngularJS

Question

The function .then is not compatible with AngularJS

I have a service that is responsible for loading data.

 angular.module('App').service('daysService', ['$http','$q',function($http,$q) {

    var days = [];

      return {
                 loadDay: function() {
                    $http({
                    method: 'get',
                    url: '/app/days/list/',
                  }).success(function(data) {              
                    days.push(data);
                    return days;  
                  }).error(function (data) {
                      console.log('Error while checking server.');
                  });
                }
            };

      }]);

In the controller, I am calling this service like so:

daysService.loadDay.then(function(data) {
   alert(data)
});

However, I am encountering the following error:

TypeError: daysService.loadDay.then is not a function

Do you have any suggestions on how to resolve this issue?

javascript angularjs

Answer 1

Answer №1

Your loadDay function is missing a return statement. Here's an updated version:

return {
    loadDay: function() {
        return $http({   // <-- ensure to return the promise
            method: 'get',
            url: '/app/days/list/',
        }).success(function(data) {              
            days.push(data);
            return days;  
        }).error(function (data) {
            console.log('Error connecting to server.');
        });
    }
 };

Answer 2

Your loadDay function is missing a return statement. Here's an updated version:

return {
    loadDay: function() {
        return $http({   // <-- ensure to return the promise
            method: 'get',
            url: '/app/days/list/',
        }).success(function(data) {              
            days.push(data);
            return days;  
        }).error(function (data) {
            console.log('Error connecting to server.');
        });
    }
 };

Answer 3

Answer №2

daysService.fetchDay.then(function(response) {
   alert(response)
});

The issue here is that on the first line, you are trying to access fetchDay as a property instead of calling it like a function. To correct this, make sure to include parentheses when invoking the function:

 daysService.fetchDay().then(function(response) {
   alert(response)
});

Additionally, it seems like you are treating the service as if it were a factory. You have two options to fix this:

angular.module('App').service('daysService', ['$http','$q',function($http,$q) {   
    var days = [];

    this.fetchDay = function() {
                    $http({
                    method: 'get',
                    url: '/app/days/list/',
                  }).success(function(response) {              
                    days.push(response);
                    return days;  
                  }).error(function (response) {
                      console.log('Error while communicating with server.');
                  });
                };
      }]);

OR

angular.module('App').factory('daysService', ['$http','$q',function($http,$q) {
  var days = [];

  return {
             fetchDay: function() {
                $http({
                method: 'get',
                url: '/app/days/list/',
              }).success(function(response) {              
                days.push(response);
                return days;  
              }).error(function (response) {
                  console.log('Error while communicating with server.');
              });
            }
        };

  }]);

Lastly, don't forget to return the promise from the function:

function() {
    return $http({
        method: 'get',
        url: '/app/days/list/',
    }).success(function(response) {
        days.push(response);
        return days;
    }).error(function(response) {
        console.log('Error while communicating with server.');
    });
};

If I were implementing this, I would do:

angular.module('App').factory('daysService', ['$http', '$q', function($http, $q) {
    var days = [];

    this.fetchDay = function() {
        return $http.get('/app/days/list/').then(
            function(response) {
              days.push(response);
              return days;
            },
            function(response) {
              console.log('Error while communicating with server.');
            }
        );
    };
}]);

Answer 4

daysService.fetchDay.then(function(response) {
   alert(response)
});

The issue here is that on the first line, you are trying to access fetchDay as a property instead of calling it like a function. To correct this, make sure to include parentheses when invoking the function:

 daysService.fetchDay().then(function(response) {
   alert(response)
});

Additionally, it seems like you are treating the service as if it were a factory. You have two options to fix this:

angular.module('App').service('daysService', ['$http','$q',function($http,$q) {   
    var days = [];

    this.fetchDay = function() {
                    $http({
                    method: 'get',
                    url: '/app/days/list/',
                  }).success(function(response) {              
                    days.push(response);
                    return days;  
                  }).error(function (response) {
                      console.log('Error while communicating with server.');
                  });
                };
      }]);

OR

angular.module('App').factory('daysService', ['$http','$q',function($http,$q) {
  var days = [];

  return {
             fetchDay: function() {
                $http({
                method: 'get',
                url: '/app/days/list/',
              }).success(function(response) {              
                days.push(response);
                return days;  
              }).error(function (response) {
                  console.log('Error while communicating with server.');
              });
            }
        };

  }]);

Lastly, don't forget to return the promise from the function:

function() {
    return $http({
        method: 'get',
        url: '/app/days/list/',
    }).success(function(response) {
        days.push(response);
        return days;
    }).error(function(response) {
        console.log('Error while communicating with server.');
    });
};

If I were implementing this, I would do:

angular.module('App').factory('daysService', ['$http', '$q', function($http, $q) {
    var days = [];

    this.fetchDay = function() {
        return $http.get('/app/days/list/').then(
            function(response) {
              days.push(response);
              return days;
            },
            function(response) {
              console.log('Error while communicating with server.');
            }
        );
    };
}]);

Answer 5

Answer №3

To properly utilize the .then() method, it is recommended that your factory returns a promise instead of just the value for days. Try modifying your code to include return $q.when(days) rather than simply returning days.

Furthermore, please be aware that in Angular 1.4 and later versions, the use of .success() and .failure() callbacks has been deprecated. The preferred approach now involves using the .then() method with the following structure:

$http({stuff}).then(function successCallback(response) {
    // handle success
  }, function errorCallback(response) {
    // handle error
  });

Answer 6

To properly utilize the .then() method, it is recommended that your factory returns a promise instead of just the value for days. Try modifying your code to include return $q.when(days) rather than simply returning days.

Furthermore, please be aware that in Angular 1.4 and later versions, the use of .success() and .failure() callbacks has been deprecated. The preferred approach now involves using the .then() method with the following structure:

$http({stuff}).then(function successCallback(response) {
    // handle success
  }, function errorCallback(response) {
    // handle error
  });

Answer 7

Answer №4

 const app = angular.module('App');

app.service('daysService', ['$http','$q',function($http,$q) {

var days = [];

return {
loadDay: function() {
$http({
method: 'get',
url: '/app/days/list/',
}).success(function(data) {              
days.push(data);
//return days;  
}).error(function (data) {
console.log('Error checking server.');
});
}, getDays: function(){ return days; }
};

}]);

const myDaysService = new daysService();
myDaysService.loadDay(); $window.alert(myDaysService.getDays());

Answer 8

 const app = angular.module('App');

app.service('daysService', ['$http','$q',function($http,$q) {

var days = [];

return {
loadDay: function() {
$http({
method: 'get',
url: '/app/days/list/',
}).success(function(data) {              
days.push(data);
//return days;  
}).error(function (data) {
console.log('Error checking server.');
});
}, getDays: function(){ return days; }
};

}]);

const myDaysService = new daysService();
myDaysService.loadDay(); $window.alert(myDaysService.getDays());

Answer 9

Answer №5

To utilize the .then() method, you must first create a promise. Refer to this guide for creating a promise in AngularJS: https://docs.angularjs.org/api/ng/service/$q.

If your current code is unable to use .then() and lacks an object/object property, you may encounter the error message

TypeError: daysService.loadDay.then is not a function

. Alternatively, consider writing code that does not rely on .then() but still functions as intended through regular triggering methods.

/* Within your service */
angular.module('App').factory('daysService', ['$http',function($http) {

    var days = [];

      return {
                 loadDay: function() {
                    $http({
                    method: 'get',
                    url: '/app/days/list/',
                  }).success(function(data) {              
                    days.push(data);
                    return days;  
                  }).error(function (data) {
                      console.log('Error checking server.');
                      return;
                  });
                }
            };

      }]);

/* In your controller, trigger the event or click */
$scope.trigger = function(){
$scope.modelname = daysService.loadDay(); /* returns days if available, else returns undefined or null */
alert($scope.modelname); /* Address any potential issues with array of objects */
}

Answer 10

To utilize the .then() method, you must first create a promise. Refer to this guide for creating a promise in AngularJS: https://docs.angularjs.org/api/ng/service/$q.

If your current code is unable to use .then() and lacks an object/object property, you may encounter the error message

TypeError: daysService.loadDay.then is not a function

. Alternatively, consider writing code that does not rely on .then() but still functions as intended through regular triggering methods.

/* Within your service */
angular.module('App').factory('daysService', ['$http',function($http) {

    var days = [];

      return {
                 loadDay: function() {
                    $http({
                    method: 'get',
                    url: '/app/days/list/',
                  }).success(function(data) {              
                    days.push(data);
                    return days;  
                  }).error(function (data) {
                      console.log('Error checking server.');
                      return;
                  });
                }
            };

      }]);

/* In your controller, trigger the event or click */
$scope.trigger = function(){
$scope.modelname = daysService.loadDay(); /* returns days if available, else returns undefined or null */
alert($scope.modelname); /* Address any potential issues with array of objects */
}

The function .then is not compatible with AngularJS

Answer №1

Answer №2

Answer №3

Answer №4

Answer №5

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