等待多个承诺完成 [英] Wait for multiple promises to finish

问题描述

我正在使用Ionic平台上的SQLStorage. remove函数返回一个promise.在我的代码中，我需要删除多个值.这些都完成后，我需要执行一些代码.

I am using the SQLStorage from the Ionic platform. The remove function returns a promise. In my code I need to remove multiple values. When these are all finished I need to execute some code.

如何等待所有这些，然后执行回调函数?

How can I wait for all of these and then execute a callback function?

代码:

removeAll() {    
  this.storage.remove(key1);
  this.storage.remove(key2);
  this.storage.remove(key3);    
}

全部嵌套是一种不好的做法，所以我正在寻找一个不错的解决方案:)

Nesting all is a bad practise so I am looking for a decent solution :)

removeAll() {
  return this.storage.remove(key1).then(() => {
    this.storage.remove(key2).then(() => {
      this.storage.remove(key3);        
    });
  });
};

推荐答案

您可以使用

removeAll() {
  Promise.all([
    this.storage.remove(key1),
    this.storage.remove(key2),
    this.storage.remove(key3),
  ]).then(value => doSomething());

另请参见 https://developer.mozilla.org/en/docs /Web/JavaScript/参考/Global_Objects/Promise/all

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