React-使用combineReducers完成对数据对拆分管理

　　数据都放在reducer.js下不利于对数据进行管理，可以把一个大的reducer.js拆分成多个小的reducer.js。

　　小的reducer.js

const defaultState={
    focused:false
}
export default(state=defaultState,action)=>{
    if(action.type=='input_focus'){
        return {focused:true}
    }
    if(action.type=='input_blur'){
        return {focused:false}
    }
    return state;
}

　　大的reducer.js

import {combineReducers} from 'redux'
import {reducer as headerReducer} from '../common/header/store'
const reducer=combineReducers({
    header:headerReducer
});
 export default reducer;

　　注意在组件中使用“state.header.focused”而不是“state.focused”

const mapStateToProps = (state) => {
    return {
    focused:state.header.focused
    }
}