javascript – 为什么’this’在这个TypeScript片段中引用’window’？

鉴于这段代码：

module movieApp {
    export interface IHomeControllerScope extends ng.IScope {
        moviesToDownload: string[];
        active: string;

        deleteMovieFromDownloadList(movie: any);

        markMovieAsDownloaded(movie: any);
    }

    export class HomeController {
        public static $inject = [
            '$scope',
            '$location',
            'MovieService'
        ];

        constructor(private $scope: IHomeControllerScope, private $location: ng.ILocationService, private MovieService) {
            this.$scope.$on('$locationChangeSuccess', (event) => {
                this.setActiveUrlPart();
            });

            MovieService.getMoviesToDownload().then(response => {
                this.$scope.moviesToDownload = response;
            });
        }

        private setActiveUrlPart() {
            var parts = this.$location.path().split('/');
            this.$scope.active = parts[1];
        }

        public get moviesToDownload() {
            return this.$scope.moviesToDownload;
        }

        public markMovieAsDownloaded(movie: any) {
            movie.Downloaded = true;
        }

        public deleteMovieFromDownloadList(movie: any) {
            this.MovieService.deleteMovieFromDownloadList(movie).then(() => {
                debugger;
                this.$scope.moviesToDownload = _.without(this.$scope.moviesToDownload, movie);
            });
        }
    }
}

app.controller("HomeController", movieApp.HomeController);

一切正常,但在行中的deleteMovieFromDownloadList方法.$scope.moviesToDownload = _.without(this.$scope.moviesToDownload,movie);,这是指窗口对象,而不是我期望的实际对象.

生成的JavaScript如下所示：

var movieApp;
(function (movieApp) {
    var HomeController = (function () {
        function HomeController($scope, $location, MovieService) {
            var _this = this;
            this.$scope = $scope;
            this.$location = $location;
            this.MovieService = MovieService;
            this.$scope.$on('$locationChangeSuccess', function (event) {
                _this.setActiveUrlPart();
            });

            MovieService.getMoviesToDownload().then(function (response) {
                _this.$scope.moviesToDownload = response;
            });
        }
        HomeController.prototype.setActiveUrlPart = function () {
            var parts = this.$location.path().split('/');
            this.$scope.active = parts[1];
        };

        Object.defineProperty(HomeController.prototype, "moviesToDownload", {
            get: function () {
                return this.$scope.moviesToDownload;
            },
            enumerable: true,
            configurable: true
        });

        HomeController.prototype.markMovieAsDownloaded = function (movie) {
            movie.Downloaded = true;
        };

        HomeController.prototype.deleteMovieFromDownloadList = function (movie) {
            var _this = this;
            this.MovieService.deleteMovieFromDownloadList(movie).then(function () {
                debugger;
                _this.$scope.moviesToDownload = _.without(_this.$scope.moviesToDownload, movie);
            });
        };
        HomeController.$inject = [
            '$scope',
            '$location',
            'MovieService'
        ];
        return HomeController;
    })();
    movieApp.HomeController = HomeController;
})(movieApp || (movieApp = {}));

app.controller("HomeController", movieApp.HomeController);
//# sourceMappingURL=HomeController.js.map

如您所见,在生成的JS中,特定方法使用_this.这看起来是对的,对吗？

有人可以向我解释发生了什么以及如何解决这个问题？

编辑：

我将它与Angular结合使用：

<body data-ng-app="movieApp" data-ng-controller="HomeController as homeCtrl">
  <div class="col-sm-1">
    <i class="fa fa-trash-o" data-ng-click="homeCtrl.deleteMovieFromDownloadList(m)" title="Verwijder uit lijst"></i>
  </div>
</body>

编辑二：
在尝试了所有的建议,然后设置回我在这里发布的原始代码之后,一切正常！我不知道如何,但我想这与Chrome / VS 2013有关.无论如何,感谢那些试图帮助我的人.

解决方法:

可能“deleteMovie …”函数绑定到按钮或其他UI元素.在这种情况下,此函数在窗口上下文中执行.要解决此问题,您应该在控制器的构造函数中定义函数体：

constructor(private $scope: IHomeControllerScope, private $location: ng.ILocationService, private MovieService) {
// other initialization code...

this.deleteMovieFromDownloadList = (movie: any) => {
    this.MovieService.deleteMovieFromDownloadList(movie).then(() => {
        debugger;
        this.$scope.moviesToDownload = _.without(this.$scope.moviesToDownload, movie);
    });
  }
}

并在您的控制器类中声明适当的函数：

deleteMovieFromDownloadList: (movie: any) => void;

原文地址：https://codeday.me/bug/20190830/1766388.html

javascript – 为什么’this’在这个TypeScript片段中引用’window’？

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