AngularJS와 $ http를 동기화하는 방법

AngularJS와 $ http를 동기화하는 방법

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내 초보자 질문에 대해 죄송하지만 AngularJS 설명서는 몇 가지 기본 사항을 파악하기 위해 명시 적이거나 광범위하지 않습니다.

AngularJS와 동기식 호출을 수행하는 방법이 있습니까?

서비스에서 :

myService.getByID = function (id) {
    var retval = null;

    $http({
        url: "/CO/api/products/" + id,
        method: "GET"
    }).success(function (data, status, headers, config) {

        retval = data.Data;

    });

    return retval;
}

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현재는 아닙니다. 소스 코드 를 살펴보면 (이 시점부터 2012 년 10 월 시점) XHR open에 대한 호출이 실제로 비동기식으로 하드 코딩되어 있음을 알 수 있습니다 (세 번째 매개 변수는 true).

 xhr.open(method, url, true);

동기식 호출을 수행 한 고유 한 서비스를 작성해야합니다. 일반적으로 JavaScript 실행의 특성으로 인해 다른 모든 것을 차단하게됩니다.

...하지만 .. 다른 모든 것을 차단해야하는 경우 약속과 $ q 서비스를 살펴 봐야 합니다 . 이를 통해 일련의 비동기 작업이 완료 될 때까지 기다렸다가 모두 완료되면 무언가를 실행할 수 있습니다. 유스 케이스가 무엇인지 모르지만 살펴볼 가치가 있습니다.

그 외에, 직접 롤링하려는 경우 동기식 및 비동기식 아약스 호출 방법에 대한 자세한 정보는 여기를 참조하십시오 .

도움이 되길 바랍니다.

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Google지도 자동 완성과 약속이있는 공장에서 일했습니다.

http://jsfiddle.net/the_pianist2/vL9nkfe3/1/

이 요청으로 autocompleteService를 출고 전에 $ http incuida로 바꾸면됩니다.

app.factory('Autocomplete', function($q, $http) {

와 $ http 요청

 var deferred = $q.defer();
 $http.get('urlExample').
success(function(data, status, headers, config) {
     deferred.resolve(data);
}).
error(function(data, status, headers, config) {
     deferred.reject(status);
});
 return deferred.promise;

<div ng-app="myApp">
  <div ng-controller="myController">
  <input type="text" ng-model="search"></input>
  <div class="bs-example">
     <table class="table" >
        <thead>
           <tr>
              <th>#</th>
              <th>Description</th>
           </tr>
        </thead>
        <tbody>
           <tr ng-repeat="direction in directions">
              <td>{{$index}}</td>
              <td>{{direction.description}}</td>
           </tr>
        </tbody>
     </table>
  </div>

'use strict';
 var app = angular.module('myApp', []);

  app.factory('Autocomplete', function($q) {
    var get = function(search) {
    var deferred = $q.defer();
    var autocompleteService = new google.maps.places.AutocompleteService();
    autocompleteService.getPlacePredictions({
        input: search,
        types: ['geocode'],
        componentRestrictions: {
            country: 'ES'
        }
    }, function(predictions, status) {
        if (status == google.maps.places.PlacesServiceStatus.OK) {
            deferred.resolve(predictions);
        } else {
            deferred.reject(status);
        }
    });
    return deferred.promise;
};

return {
    get: get
};
});

app.controller('myController', function($scope, Autocomplete) {
$scope.$watch('search', function(newValue, oldValue) {
    var promesa = Autocomplete.get(newValue);
    promesa.then(function(value) {
        $scope.directions = value;
    }, function(reason) {
        $scope.error = reason;
    });
 });

});

the question itself is to be made on:

deferred.resolve(varResult); 

when you have done well and the request:

deferred.reject(error); 

when there is an error, and then:

return deferred.promise;

---

var EmployeeController = ["$scope", "EmployeeService",
        function ($scope, EmployeeService) {
            $scope.Employee = {};
            $scope.Save = function (Employee) {                
                if ($scope.EmployeeForm.$valid) {
                    EmployeeService
                        .Save(Employee)
                        .then(function (response) {
                            if (response.HasError) {
                                $scope.HasError = response.HasError;
                                $scope.ErrorMessage = response.ResponseMessage;
                            } else {

                            }
                        })
                        .catch(function (response) {

                        });
                }
            }
        }]


var EmployeeService = ["$http", "$q",
            function ($http, $q) {
                var self = this;

                self.Save = function (employee) {
                    var deferred = $q.defer();                
                    $http
                        .post("/api/EmployeeApi/Create", angular.toJson(employee))
                        .success(function (response, status, headers, config) {
                            deferred.resolve(response, status, headers, config);
                        })
                        .error(function (response, status, headers, config) {
                            deferred.reject(response, status, headers, config);
                        });

                    return deferred.promise;
                };

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I recently ran into a situation where I wanted to make to $http calls triggered by a page reload. The solution I went with:

1. Encapsulate the two calls into functions
2. Pass the second $http call as a callback into the second function
3. Call the second function in apon .success

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Here's a way you can do it asynchronously and manage things like you would normally. Everything is still shared. You get a reference to the object that you want updated. Whenever you update that in your service, it gets updated globally without having to watch or return a promise. This is really nice because you can update the underlying object from within the service without ever having to rebind. Using Angular the way it's meant to be used. I think it's probably a bad idea to make $http.get/post synchronous. You'll get a noticeable delay in the script.

app.factory('AssessmentSettingsService', ['$http', function($http) {
    //assessment is what I want to keep updating
    var settings = { assessment: null };

    return {
        getSettings: function () {
             //return settings so I can keep updating assessment and the
             //reference to settings will stay in tact
             return settings;
        },
        updateAssessment: function () {
            $http.get('/assessment/api/get/' + scan.assessmentId).success(function(response) {
                //I don't have to return a thing.  I just set the object.
                settings.assessment = response;
            });
        }
    };
}]);

    ...
        controller: ['$scope', '$http', 'AssessmentSettingsService', function ($scope, as) {
            $scope.settings = as.getSettings();
            //Look.  I can even update after I've already grabbed the object
            as.updateAssessment();

And somewhere in a view:

<h1>{{settings.assessment.title}}</h1>

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Since sync XHR is being deprecated, it's best not to rely on that. If you need to do a sync POST request, you can use the following helpers inside of a service to simulate a form post.

It works by creating a form with hidden inputs which is posted to the specified URL.

//Helper to create a hidden input
function createInput(name, value) {
  return angular
    .element('<input/>')
    .attr('type', 'hidden')
    .attr('name', name)
    .val(value);
}

//Post data
function post(url, data, params) {

    //Ensure data and params are an object
    data = data || {};
    params = params || {};

    //Serialize params
    const serialized = $httpParamSerializer(params);
    const query = serialized ? `?${serialized}` : '';

    //Create form
    const $form = angular
        .element('<form/>')
        .attr('action', `${url}${query}`)
        .attr('enctype', 'application/x-www-form-urlencoded')
        .attr('method', 'post');

    //Create hidden input data
    for (const key in data) {
        if (data.hasOwnProperty(key)) {
            const value = data[key];
            if (Array.isArray(value)) {
                for (const val of value) {
                    const $input = createInput(`${key}[]`, val);
                    $form.append($input);
                }
            }
            else {
                const $input = createInput(key, value);
                $form.append($input);
            }
        }
    }

    //Append form to body and submit
    angular.element(document).find('body').append($form);
    $form[0].submit();
    $form.remove();
}

Modify as required for your needs.

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What about wrapping your call in a Promise.all() method i.e.

Promise.all([$http.get(url).then(function(result){....}, function(error){....}])

According to MDN

Promise.all waits for all fulfillments (or the first rejection)

참고URL : https://stackoverflow.com/questions/13088153/how-to-http-synchronous-call-with-angularjs