2

此处的代码使用动作加载数据并且是系列的,但是很难编辑此代码添加另一个 API 加载,并且语法不清楚。

this.props.loadNutMatrixes({perPage:'all'}).then(()=>{
      this.props.loadIngredients().then(()=>{
        this.props.getBadge().then(()=>{
          this.props.loadNutInfoItems({perPage:'all'}).then(()=>{
            this.props.getItemSize().then(()=>{
              this.props.getSingleMenuCategory(this.props.category_uid).then(()=>{
                this.props.loadAllStores(({per_page:'all'})).then(()=>{
                  if (this.props.selectedMenuItem ){
                    initialize("addNewMenuItem", {
                      ...this.props.selectedMenuItem
                    })
                  }
                })
              })
            })
          })
        })
      })
    })

4

3 回答 3

5

您可以通过链接承诺而不是嵌套将其转换为垂直结构:

this.props.loadNutMatrixes({perPage:'all'})
  .then(() => this.props.loadIngredients())
  .then(() => this.props.getBadge())
  .then(() => this.props.loadNutInfoItems({perPage:'all'}))
  .then(() => this.props.getItemSize())
  .then(() => this.props.getSingleMenuCategory(this.props.category_uid))
  .then(() => this.props.loadAllStores(({per_page:'all'})))
  .then(() => {
    if (this.props.selectedMenuItem) {
      initialize("addNewMenuItem", {
        ...this.props.selectedMenuItem
      })
    }
  });

一个可能的改进可能是将所有接收参数的创建承诺的函数包装到没有参数的函数中,并将它们传递为props

loadAllNutMatrixes() {
  return this.loadNutMatrixes({ perPage: 'all' });
}

loadAllNutInfoItems() {
  return this.loadNutInfoItems({ perPage: 'all' });
}

getSingleMenuCategoryFromId() {
  return this.getSingleMenuCategory(this.category_uid);
}

loadEveryStory() {
  return this.loadAllStores({ perPage: 'all' });
}

然后您可以将最后一步重构为自己的方法:

onChainFinished() {
  if (this.props.selectedMenuItem) {
    initialize("addNewMenuItem", {
      ...this.props.selectedMenuItem
    })
  }
}

并将两者与一些解构结合起来以实现更清洁的链:

const { props } = this;
props.loadAllNutMatrixes()
  .then(props.loadIngredients)
  .then(props.getBadge)
  .then(props.loadAllNutInfoItems)
  .then(props.getItemSize)
  .then(props.getSingleMenuCategoryFromId)
  .then(props.loadEveryStore)
  .then(this.onChainFinished);

根据您的评论进行编辑

使用 promise.all 之类的东西,但以串联方式!

没有本地方法来链接 Promises,但您可以构建一个适合您的用例的辅助方法来执行此操作。这是一个通用示例:

// `cp` is a function that creates a promise and 
// `args` is an array of arguments to pass into `cp`
chainPromises([
  { cp: this.props.loadNutMatrixes, args: [{perPage:'all'}] },
  { cp: this.props.loadIngredients },
  { cp: this.props.getBadge },
  { cp: this.props.loadNutInfoItems, args: [{perPage:'all'}] },
  { cp: this.props.getItemSize },
  { cp: this.props.getSingleMenuCategory, args: [this.props.category_uid] },
  { cp: this.props.loadAllStores, args: [{per_page:'all'}] }
]).then(() => {
  if (this.props.selectedMenuItem) {
    initialize("addNewMenuItem", {
      ...this.props.selectedMenuItem
    })
  }
});

function chainPromises(promises) {
  return promises.reduce(
    (chain, { cp, args = [] }) => {
      // append the promise creating function to the chain
      return chain.then(() => cp(...args));
    }, Promise.resolve() // start the promise chain from a resolved promise
  );
}

如果您使用与上述相同的方法来重构带有参数的方法,它也会清理此代码:

const { props } = this;
chainPropsPromises([
  props.loadAllNutMatrixes,
  props.loadIngredients,
  props.getBadge,
  props.loadAllNutInfoItems,
  props.getItemSize,
  props.getSingleMenuCategoryFromId,
  props.loadEveryStory
])
.then(this.onChainFinished);

function chainPropsPromises(promises) {
  return promises.reduce(
    (chain, propsFunc) => (
      chain.then(() => propsFunc());
    ), Promise.resolve()
  );
}
于 2016-10-08T07:39:07.113 回答
0

返回承诺以将其链接到外部承诺。

this.props.loadNutMatrixes({perPage:'all'}).then(()=>{
  return this.props.loadIngredients()
})
.then(()=>{
  return this.props.getBadge()
})
.then(()=>{
  return this.props.loadNutInfoItems({perPage:'all'})
})
.then(()=>{
  return this.props.getItemSize()
})
.then(()=>{
  return this.props.getSingleMenuCategory(this.props.category_uid)
});

...
于 2016-10-08T07:38:51.367 回答
0

如果承诺不相互依赖,我会使用Promise.all

const {props} = this;
Promise.all([
    props.loadNutMatrixes({perPage: 'all'}),
    props.loadIngredients(),
    props.getBadge(),
    props.loadNutInfoItems({perPage: 'all'}),
    props.getItemSize(),
    props.getSingleMenuCategory(props.category_uid),
    props.loadAllStores(({per_page: 'all'})),
]).then(() => {
    if (props.selectedMenuItem) initialize("addNewMenuItem", {...props.selectedMenuItem});
});
于 2016-10-08T07:39:54.930 回答