Question

我正在使用typescript实现一个简单的角度应用程序。
我将服务引用传递给控制器，但是当我尝试调用服务的方法时，我得到一个异常，说服务引用是未定义的。 “dataAccessLayer”模块在“clinicManager”模块（控制器所属的模块）中正确添加为依赖项。
我的服务：

module app.dal{

interface IDataAccessService{
    get(id:number):app.Model.IPatient;
}

export class DataAccessService implements IDataAccessService{
    private _db : Loki;

    static $inject = ['Loki'];
    constructor(private Loki:Loki) {
        this._db = new Loki('./database/db.json',{
            autosave: true,
            autosaveInterval : 3000 // 3 secs
        });
    }

    get(id:number):app.Model.IPatient {

          // Implementation here...
        }
    }

angular.module('dataAccessLayer',['lokijs'])
    .service('dataAccessService',['Loki',DataAccessService]);
}

控制器：

module app.PatientDetails{

interface IPatientDetails{
    patient: app.Model.IPatient;
}

import accessLayer = app.dal.DataAccessService;

export class PatientDetailsCtrl implements IPatientDetails{

    private dataAccessService: accessLayer;

    static $inject = ['patient','dataAccessService'];
    constructor(public patient:app.Model.IPatient, dataAccessService:accessLayer){
        this.dataAccessService = dataAccessService;

        // -> TypeError: Cannot read property 'get' of undefined
        var patient = dataAccessService.get(1);

    }
}

  angular.module('clinicManager')
         .controller('patientDetailsCtrl',['dataAccessService',PatientDetailsCtrl]);
 }

app.js

angular.module('clinicManager',['ngMaterial','dataAccessLayer']);

的index.html

<!-- Application scripts-->
<script src="app.js"></script>

<!-- Services-->
<script src="DataAccessLayer/DataAccessService.js"></script>

<!-- Controllers-->
<script src="Controllers/PatientDetailsCtrl.js"></script>

Answer 1

如果我在控制器中删除了对Patient的引用，该服务可以正常实例化，该服务正常工作。我在这里放置代码以更好地显示格式：

module app.PatientDetails{

interface IPatientDetails{
     // patient: app.Model.IPatient;
 }

import accessLayer = app.dal.DataAccessService;

export class PatientDetailsCtrl implements IPatientDetails{

    private dataAccessService: accessLayer;

    static $inject = [/*'patient',*/'dataAccessService'];
    constructor(/*public patient:app.Model.IPatient,*/ dataAccessService:accessLayer){
        this.dataAccessService = dataAccessService;

    // The function is now called properly
    var patient = dataAccessService.get(1);

   }
}

  angular.module('clinicManager')
         .controller('patientDetailsCtrl', ['dataAccessService',PatientDetailsCtrl]);
}

在typescript中编写的Angular服务在控制器中是未定义的

1 个答案: