键入'Budget[]‘不能指定键入'Promise<Budget[]>’Property‘，那么'Budget[]’类型中缺少‘

Question

我要回Promise<Budget[]>。但它显示错误为：

ts类型'Budget[]‘不能指定键入’承诺‘。 属性‘in’在'Budget[]‘类型中缺失。让预算: Budget[]

您能告诉我如何从下面的方法返回Promise<Budget[]>吗？

 createBudgets(data: Budget[], projectId: string): Promise<Budget[]> {
    let budgets: Budget[] = [];
    forEach(data, async (d) => {
      const budgetId: string = this.fireStore.createId();
      d.id = budgetId;
      budgets.push(d);
      await this.fireStore.doc<Budget>(`projects/${projectId}/budgets/${budgetId}`).set({
        id: budgetId,
        amount: d.amount,
        contingency: d.contingency,
        budgetGroup: d.budgetGroup,
        creationTime: moment().format()
      });
    });
    return budgets;// error shows here?
  }

Answer 1

如果要等待所有set方法调用完成执行，则需要将它们添加到数组中，并使用Promise.all等待它们完成：

async createBudgets(data: Budget[], projectId: string): Promise<Budget[]> {
    let budgets : Budget[] = [];
    await Promise.all(data.map(async (d) => {
        const budgetId: string = this.fireStore.createId();
        d.id = budgetId;
        budgets.push(d);
        await this.fireStore.doc<Budget>(`projects/${projectId}/budgets/${budgetId}`).set({
            id: budgetId,
            amount: d.amount,
            contingency: d.contingency,
            budgetGroup: d.budgetGroup,
            creationTime: moment().format()
        });
    }));
    return budgets;
}