当服务中的数据准备就绪时如何做某事？

Question

我创建这样的服务：

export class MDCurrencyService implements IMDCurrencyService {

        httpService: ng.IHttpService;
        handlerUrl: string;

        constructor($http: ng.IHttpService) {
            this.httpService = $http;
            this.handlerUrl = '/Master/';
        }


        get(): MDCurrency[]{
            var result: MDCurrency[] = [];

            var resp: ng.IPromise<any> = this.httpService.get(this.handlerUrl +'GetAllCurrency')
                .then((response: any): ng.IPromise<any> => this.handlerResponded(response, null));
            resp.then((data) => {
                if (data.is_success) {
                    data.data.forEach(c => {
                        var converted: MDCurrency = <MDCurrency>c;
                        converted.selectedCountry = null;
                        converted.selectedStatus = null;
                        result.push(converted);
                    });
                    return result;
                }
                else return null;

            });
            return result;
        }

        handlerResponded(response: any, params: any): any {
            response.data.requestParams = params;
            return response.data;
        }




    }

在controller：

中

$scope.currencies = this.currencies = mdCurrencyService.get();
            if ($scope.currencies.length > 0) {
                console.log('entered'); //never executed
                $scope.currencies.forEach(currency => {
                    for (var ii = 0; ii < this.statuses.length; ii++)
                        if ($scope.statuses[ii].Id == currency.Status)
                            currency.selectedStatus = this.statuses[ii];
                });
            }

但是$scope.currencies从服务中填充forEach从未执行过。 当$scope.currencies被来自服务的数据填充时如何执行该代码？

Answer 1

mdCurrencyService.get()应该作为返回promise的异步服务来实现。它可以这样使用：

mdCurrencyService.get().then(function (currencies) {
    // process result here
    $scope.currencies = currencies;
});