我想知道mapDispatchToProps今天是否还有一点用处。我正在研究redux文档教程（以构建待办事项列表），其中VisibleTodoList描述为：

import { connect } from 'react-redux'
import { toggleTodo } from '../actions'
import TodoList from '../components/TodoList'

const getVisibleTodos = (todos, filter) => {
  switch (filter) {
    case 'SHOW_ALL':
      return todos
    case 'SHOW_COMPLETED':
      return todos.filter(t => t.completed)
    case 'SHOW_ACTIVE':
      return todos.filter(t => !t.completed)
  }
}

const mapStateToProps = (state) => {
  return {
    todos: getVisibleTodos(state.todos, state.visibilityFilter)
  }
}

const mapDispatchToProps = (dispatch) => {
  return {
    onTodoClick: (id) => {
      dispatch(toggleTodo(id))
    }
  }
}

const VisibleTodoList = connect(
  mapStateToProps,
  mapDispatchToProps
)(TodoList)

export default VisibleTodoList

但是，有人告诉我，今天，我根本无法通过以下方式定义mapDispatchToProps和连接所有内容：

const VisibleTodoList = connect(
  mapStateToProps,
  toggleTodo
)(TodoList)

这样对吗？如果是这样，写一个“ a”有mapDispatchToProps什么意义？简单地返回动作有什么弊端吗？

谢谢！