Question

我有一个角度4的应用程序，我正在尝试编写一个行动队列。在上一个函数完成后将触发每个动作并获取其参数。

＆＃13;

public activeRegistrationAndSync() {
    let actionsToPerformByOrder = [
       () => this.registrationComponent.activeFormValidators.apply(null, arguments),
       () => this.registrationComponent.register.apply(null, arguments),
       () => this.autoLogin.apply(null, arguments),
       () => this.postLogin.apply(null, arguments),
       () => this.checkout.apply(null, arguments)
    ];

    let defer = new Deferred<void>();
    let curPromise = defer.promise;

    //Build chain of acitons
    actionsToPerformByOrder.forEach(action => {
      curPromise = curPromise
        .then(action)
        .catch(err => this.error.emit(err));
    })

    //Active actions
    defer.resolve();
 }
 
 
 export class Deferred<T> {
  promise: Promise<T>;
  resolve: (value?: T | PromiseLike<T>) => void;
  reject:  (reason?: any) => void;

  constructor() {
    this.promise = new Promise<T>((resolve, reject) => {
      this.resolve = resolve;
      this.reject  = reject;
    });
  }
}

＆＃13;

我的问题是箭头函数不支持参数，而是使用function（）{}而不是更改此引用。

Answer 1

我建议您使用async/await来合并并运行您的操作。它很容易阅读，这是基本的想法，用你的具体情况修改它：

async function activeRegistrationASync() {
  const actionsToPerformByOrder = [
    async (r) => {
      return Promise.resolve(3)
    },
    async (r) => {
      return Promise.resolve(r + 5)
    }
  ];

  let result;
  for (let action of actionsToPerformByOrder) {
    result = await action(result);
  }
  return result;
}

activeRegistrationASync().then((r) => {
  console.log(r);
});

Answer 2

您可以使用
之类的传播操作符
（... rest）=＆gt;的console.log（休息）
您可以使用bind功能

function func（/ arguments /）{console.log（this。arguments）}

让a = func.bind（this）

Angular - 如何使用带参数的箭头函数？

2 个答案: