javascript - TypeError : Object(. ..) 不是函数 reactjs

Question

我试图通过将 fillCalendar() 从组件的方法中提取到它自己的 js 文件中并导入它来清理这个 react 组件。最初 this.state.datesArray 是在 componentWillMount() 生命周期方法中设置的。现在我试图在构造函数中直接初始化它，因为这就是 react 文档 recommends .现在这样做会抛出“TypeError: Object(...) is not a function”错误，我不知道为什么。这是 Calendar.js 使用的样子 see here .

日历.js

import React, { Component } from 'react';
import { fillCalendar } from '../calendar.tools'

class Calendar extends Component {
  constructor(props) {
    super(props)
    this.state = {
      datesArray: fillCalendar(7, 2018),
      date: new Date(),
      monthIsOffset: false,
      monthOffset: new Date().getMonth(),
      yearOffset: new Date().getFullYear()
    }
  }
  render() {
    return (
      ...
    )
  }
}

日历工具.js

let fillCalendar = (month, year) => {
  let datesArray = []
  let monthStart = new Date(year,month,1).getDay()
  let yearType = false;
  let filledNodes = 0;
  // Check for leap year
  (year%4 === 0) ? 
    (year%100 === 0) ?
      (year%400) ? yearType = true : yearType = false : 
    yearType = true : 
  yearType = false
  const monthArrays = yearType ? [31,29,31,30,31,30,31,31,30,31,30,31] : [31,28,31,30,31,30,31,31,30,31,30,31]
  if (month === 0) { month = 12; }
  let leadDayStart = monthArrays[month-1] - monthStart + 1
  // Loop out lead date numbers
  for (let i = 0; i < monthStart; i++) {
    datesArray.push({date: leadDayStart, type: "leadDate", id: "leadDate" + i})
    leadDayStart++
    filledNodes++
  }
  if (month === 12) { month = 0; }
  // Loop out month's date numbers
  for (let i = 0; i < monthArrays[month]; i++) {
    datesArray.push({date: i + 1, type: "monthDate", id: "monthDate" + i})
    filledNodes++
  }
  // fill the empty remaining cells in the calendar
  let remainingNodes = 42 - filledNodes;
  for (let i = 0; i < remainingNodes; i++) {
    datesArray.push({date: i + 1, type: "postDate", id: "postDate" + i})
  }
  return datesArray
}

Answer 1

看起来不错，您只需导出您的函数即可。

使用

export let fillCalendar = (month, year) => {

代替

let fillCalendar = (month, year) => {