AngularJS -指令- onClick函数调用$http(POST) - $http是未定义的？

Question

我有一个AngularJS指令，它使用$http (ng.IHttpService)调用api中的数据，没有问题。

我将'click‘事件绑定到一个函数中，并希望调用同一个api控制器上的POST请求将一些数据放入数据库中。

这是指令

import { Advert } from "../entities";

interface AdvertScope extends ng.IScope {
    advert: Advert;
}

export class AdvertDirective implements ng.IDirective {    
    restrict = 'EA';
    templateUrl = '/AngularViews/adverts.html';
    scope = {}

    constructor(private $http: ng.IHttpService) { }

    public link = (scope: AdvertScope, elem: JQuery, attributes: ng.IAttributes, ngModel: ng.INgModelController) => {
        this.$http.get<Advert>('/api/adverts/get-adverts')
            .then(response => {
                scope.advert = response.data;
            });

        elem.bind('click', function (e: any): void {
            var advertId = e.path[0].id;

            if (advertId != null && advertId != undefined) {
                var data = { advertId: advertId };

                // This is just a fire-and-forget post - no success/error handling   
                this.$http.post('/api/adverts/log-click', JSON.stringify(data));
            }
        });        
    }

    static factory(): ng.IDirectiveFactory {
        var directive = ($http: ng.IHttpService) => new AdvertDirective($http);
        directive.$inject = ['$http']
        return directive;
    }

}

问题是，当单击事件被击中时，错误：

未定义的TypeError:无法读取未定义的属性“post”

是生成的。

Answer 1

当你写“函数”时，“这”指的是函数本身。您只需将“函数”替换为() =>{}，如下所示：

elem.bind('click',  (e: any): void=> {
    var advertId = e.path[0].id;

    if (advertId != null && advertId != undefined) {
        var data = { advertId: advertId };

        // This is just a fire-and-forget post - no success/error handling   
        this.$http.post('/api/adverts/log-click', JSON.stringify(data));
    }
});