Angular服務在執行HTTP發布時不會在控制器中返回任何數據

Question

Angular服務在執行http發布時不會在控制器中返回任何數據。

app.controller("letter_active", function ($scope, myService) {
    $scope.artist = myService.getReplyType2();
});

app.service('myService', function ($http) {

    this.getReplyType2 = function () {
        $http.post('file/getReplyType', {})
        .success(function (data, status) {
            return data;
        }).error(function (data, status) {
            alert("Error has occured" + status);
        });
    }
});

需要我幫助的新手

Answer 1

對於異步調用，您需要返回promise

this.getReplyType2 = function() {
    var defer = $q.defer();
        $http({method: 'POST', url: 'file/getReplyType', data: {}})
            .success(function(data, status, headers, config) {
                // this callback will be called asynchronously
                // when the response is available
                defer.resolve(data);
                    })
            .error(function(data, status, headers, config) {
                // called asynchronously if an error occurs
                // or server returns response with an error status.
                window.data = data;
            });

    return defer.promise;
}

app.controller("letter_active", function ($scope, myService) {
    myService.getReplyType2().then(function(data) {
        $scope.artist = data;    
    });
});

Answer 2

在Angular中，異步服務的典型工作是該服務返回一個Promise對象，並且在控制器中，您可以使用該promise的then/success方法設置范圍數據：

app.controller("letter_active", function ($scope, myService) {
    myService.getReplyType2().then(function(data) {
        $scope.artist = data;    
    });
});

app.service('myService', function ($http) {

    this.getReplyType2 = function () {
        return $http.post('file/getReplyType', {}).success(function (data, status) {
            return data;
        }).error(function (data, status) {
            alert("Error has occured" + status);
        });
    }
});

請注意，該getReplyType2方法現在返回$http.post調用的結果，這是一個Promise對象。