实现一个简单的订阅与发布模式的代码块，和redux

Posted 2020-10-27

/**
 * Created by Mrzou on 2018/3/11.
 */

//实现简单的订阅与发布模式的代码块
export function pattern() {

   let currentListeners = []

   function subscribe(type, listener) {

      if ((typeof listener !== ‘function‘) || (typeof listener !== ‘string‘)) {
         throw new Error(‘参数类型错误‘)
      } else {
         currentListeners.push({type, listener})
      }

   }

   function dispatch(type, value) {

      currentListeners.forEach(v=> {
         (v.type === type) && v.listener(value)
      })

   }

   return {subscribe, dispatch}
}


//实现一个简单的redux
export function createStore(reducer) {
   let currentState = {}
   let currentListeners = []

   function getState() {
      return currentState
   }

   function subscribe(listener) {
      currentListeners.push(listener)
   }

   function dispatch(action) {
      currentState = reducer(currentState, action)
      currentListeners.forEach(v=>v())
      return action
   }

   dispatch({type: ‘@@MONI_REDUX/INITIALSTATE‘})

   return {getState, subscribe, dispatch}
}