你好，我试图创建一个单独的文件夹为我的axios路线。我不希望他们在我的组件文件内的React。
我已经在下面的文件夹下尝试了这个，与我的组件文件夹分开。src〉actions〉authentication

import axios from 'axios';

export const signupUser = (user, history) => dispatch => {
  axios.post('http://localhost:3000/signup', user)
  console.log(user)
    .then(res => history.push('/login'))
    .catch(err => {
      console.log(err);

    });
};

在Signup.js组件中，我有以下内容，它们当前不起作用

import React, { Component } from 'react';
import { Link } from 'react-router-dom';
import { signupUser } from '../actions/authentication';
import axios from 'axios';

let today = new Date();
let date = today.getFullYear()+ '-' +  (today.getMonth()+1)+ '-' +today.getDate();



class Signup extends Component {

  constructor() {
    super()
    this.state = {
      first_name: '',
      last_name: '',
      user_name: '',
      email: '',
      password: '',
      created_on: date,
      isSignedup: false
    }

    this.handleInputChange = this.handleInputChange.bind(this);

    this.handleSubmit = this.handleSubmit.bind(this);
  }

  handleInputChange = (e) => {
    this.setState({
      [e.target.name]: e.target.value
    })
    console.log(this.state);
  }

  handleSubmit = (e) => {
    e.preventDefault();

    const user = {

      first_name: this.state.first_name,
      last_name: this.state.last_name,
      email: this.state.email,
      user_name: this.state.user_name,
      password: this.state.password,
      created_on: this.state.created_on,
      isSignedup: !this.state.isSignedup
    }
    .then(data => {
      console.log(data);
      this.props.history.replace('/login');
    })
    .catch(err => {
      console.log(err);
    })
  }

只有在我的组件〉Signup.js中，如果我在组件中有如下的实际axios路由，它才能工作：

handleSubmit = (e) => {
    e.preventDefault();

    axios.post('http://localhost:3000/signup', {

      first_name: this.state.first_name,
      last_name: this.state.last_name,
      email: this.state.email,
      user_name: this.state.user_name,
      password: this.state.password,
      created_on: this.state.created_on,
      isSignedup: !this.state.isSignedup
    })
    .then(data => {
      console.log(data);
      this.props.history.replace('/login');
    })
    .catch(err => {
      console.log(err);
    })
  }

我一直收到的错误是then不是一个函数。有人能帮我解决这个问题吗？提前谢谢。