为什么要分配一个变量'这个'在javascript中的module.export函数中

时间:2017-11-07 16:53:46

标签: javascript feathersjs

我正在尝试理解以下代码,这些代码取自在feathersjs应用程序中创建的服务。

// Initializes the `users` service on path `/users`
const createService = require('feathers-knex');
const createModel = require('../../models/users.model');
const hooks = require('./users.hooks');
const filters = require('./users.filters');

module.exports = function () {
  const app = this;
  const Model = createModel(app);
  const paginate = app.get('paginate');

  const options = {
    name: 'users',
    Model,
    paginate
  };

  // Initialize our service with any options it requires
  app.use('/users', createService(options));

  // Get our initialized service so that we can register hooks and filters
  const service = app.service('users');

  service.hooks(hooks);

  if (service.filter) {
    service.filter(filters);
  }
};

然后按如下方式导入此文件:

// many requires..
const feathers = require('feathers');
// more requires
const services = require('./services');
// other requires
const app = feathers();

有人可以解释一下这行

const app = this

在创建服务的代码中做什么?

1 个答案:

答案 0 :(得分:3)

它将this的值分配给变量(井,常量),其名称比更清楚地描述了该值。它旨在使维护人员更容易理解代码。