Question

这是我的组件/todo-list..js

import React,{Component} from 'react';
import * as uuid from 'uuid';
import { render } from '@testing-library/react';


class TodoList extends React.Component{

    state={
        text:''
    }
    onChange=(e)=>{
        this.setState({
            text:e.target.value,
        })
    }
    onClick=()=>{
        const id =uuid.v4();
        this.props.addTodo(id,this.state.text)
    }

    onDelete=()=>{

       this.props.deteleTodo(this.props.todos.id)}

    render(){

        return(
            <div>
                <ul>
                    {this.props.todos.map((todo)=>(
                        <li key={todo.id}>{todo.text}

                        <button onClick={this.onDelete}>delete</button> 
                        </li>
                    )

                    )}
                </ul>

                    <input value ={this.state.text} onChange= {this.onChange}/>
                     <button onClick={this.onClick}> Add toto</button>
            </div>
        )

    }
}
export default TodoList

这是我的动作/add-todo.js

export const addTodo =(id,text)=>({
     type:'ADD_TODO',
     payload:{id,text},
});
export const deteleTodo=(id)=>({
    type: 'REMOVE_TODO',
    payload:id
})

这是我的container / todo-list.js

import {addTodo,deteleTodo} from '../actions/add-todo'

const mapStateToProps=(state)=>({
    todos:state.todos,
})
const mapDispatchToProps=(dispatch)=> 
{
    return{
    addTodo:(id,text)=>dispatch(addTodo(id,text)),
    deteleTodo:(id)=>dispatch(deteleTodo(id))
}
}
export default connect (mapStateToProps,mapDispatchToProps)(TodoList)

这是我的reducers索引和todos.js

export default (state =[],action)=>{
    switch (action.type){
        case 'ADD_TODO':
            return[...state, action.payload];
        case 'REMOVE_TODO':
            const newState=state.filter((todo)=>todo.id !== action.payload.id);
            return newState;
        default:
            return state;
    }
}

import {combineReducers} from 'redux'
import todosReducer from './todos'

export default combineReducers({
    todos:todosReducer,
})

Answer 1

您似乎需要将待办事项的ID传递给onDelete()函数。像这样：

{this.props.todos.map((todo)=>(
        <li key={todo.id}>{todo.text}
            <button onClick={() => this.onDelete(todo.id)}>delete</button> 
        </li>
    )
)}

然后在您的onDelete()中使用它：

onDelete = (id) => { this.props.deteleTodo(id) }

Answer 2

更改为此：

export default (state =[],action)=>{
   switch (action.type){
     case 'ADD_TODO':
        return {...state, action.payload};

删除时出错：无法读取未定义的属性“ id”

2 个答案: