React实现评论的添加和删除

本文实例为大家分享了React实现评论添加和删除的具体代码，供大家参考，具体内容如下

一、效果图

二、需求描述

1. 手动输入用户名和评论内容，点击提交；输入内容被追加到右侧评论列表；

2.  点击评论列表的“删除”按钮，弹框提示确定删除用户“xx”；

3. 点击“确定”，“xx”用户发表的评论被删除；

4. 所有评论均被删除时，显示“暂无评论，点击添加评论！！！”

三、代码实现

App.js

import React from \'react\';
import \'./App.css\';
import CommentAdd from \'../src/components/CommentAdd\'
import CommentList from \'../src/components/CommentList\'
import PropTypes from \'prop-types\'
import \"../src/assets/css/bootstrap.css\"
 
class App extends React.Component {
 // 给组件对象指定state属性
 // 初始化状态
 state = {
 comments: [
  {username: \"Tom\", content: \"React太容易了\"},
  {username: \"Jack\", content: \"React太难了\"}
 ]
 }
 
 static propTypes = {
 comments: PropTypes.array.isRequired,
 addComment: PropTypes.func.isRequired,
 deleteComment: PropTypes.func.isRequired
 }
 
 addComment = (comment) => {
 // 将添加的评论追加到评论list上
 const {comments} = this.state
 comments.unshift(comment)
 // 更新状态
 this.setState({comments})
 }
 deleteComment = (index) => {
 const {comments} = this.state
 comments.splice(index, 1)
 this.setState({comments})
 }
 
 render() {
 const {comments} = this.state
 return (
  <div>
  <header className=\"site-header jumbotron\">
   <div className=\"container\">
   <div className=\"row\">
    <div className=\"col-xs-12\">
    <h2>评论管理列表</h2>
    </div>
   </div>
   </div>
  </header>
  <div className=\"container\">
   <CommentAdd addComment={this.addComment}/>
   <CommentList comments={comments} deleteComment={this.deleteComment}/>
  </div>
  </div>
 );
 }
}
 
export default App;

CommentAdd.js

import React, {Component} from \'react\';
import PropTypes from \'prop-types\'
import \"../assets/css/bootstrap.css\"
 
class CommentAdd extends Component {
 
 state = {
 username: \"\",
 content: \"\"
 }
 
 static propTypes = {
 addComment: PropTypes.func.isRequired
 }
 handleNameChange = (event) => {
 const username = event.target.value
 this.setState({username});
 }
 handleContentChange = (event) => {
 const content = event.target.value
 this.setState({content});
 }
 handleSubmit = () => {
 const comment = this.state
 this.props.addComment(comment)
 // 清楚输入数据
 this.setState({
  username: \"\",
  content: \"\"
 });
 }
 
 render() {
 const {username, content} = this.props
 return (
  <div className=\"col-md-4\">
  <form className=\"form-horizontal\">
   <div className=\"form-group\">
   <label>用户名：</label>
   <input type=\"text\" className=\"form-control\" placeholder=\"请输入用户名\" value={username}
    onChange={this.handleNameChange}/><br/>
   </div>
   <div className=\"form-group\">
   <label>评论内容：</label>
   <textarea className=\"form-control\" rows=\"6\" placeholder=\"请输入评论内容\"
     value={content} onChange={this.handleContentChange}>
   </textarea>
   </div>
   <div className=\"form-group\">
   <div className=\"col-sm-offset-2 col-sm-10\">
    <button type=\"button\" className=\"btn btn-default pull-right\"
     onClick={this.handleSubmit}>提交
    </button>
   </div>
   </div>
  </form>
  </div>
 );
 }
}
 
export default CommentAdd;

CommentList.js

import React, {Component} from \'react\';
import CommentItem from \"./CommentItem\";
import PropTypes from \'prop-types\'
import \"../assets/css/comment_list.css\"
 
class CommentList extends Component {
 
 static propTypes = {
 comments: PropTypes.array.isRequired,
 deleteComment: PropTypes.func.isRequired
 }
 
 render() {
 const {comments, deleteComment} = this.props
 const display = comments.length === 0 ? \"block\" : \"none\"
 return (
 
  <div className=\"col-md-8\">
  <h4>评论回复：</h4>
  <h5 style={{display}}>暂无评论，点击添加评论！！！</h5>
  <ul>
   {
   comments.map((comment, index) => <li key={index}><CommentItem comments={comment} index={index}
           deleteComment={deleteComment}/>
   </li>)
   }
  </ul>
  </div>
 );
 }
}
 
export default CommentList;

CommentItem.js

import React, {Component} from \'react\';
import PropTypes from \'prop-types\'
import \"../assets/css/comment_item.css\"
 
class CommentItem extends Component {
 static propTypes = {
 comments: PropTypes.array.isRequired,
 deleteComment: PropTypes.func.isRequired,
 index: PropTypes.number.isRequired
 }
 
 handleDeleteComment = () => {
 const {comments, deleteComment, index} = this.props
 if (window.confirm(`确定删除${comments.username}嘛？`)) {
  deleteComment(index)
 }
 }
 
 render() {
 const {comments} = this.props
 return (
  <div className=\"list-group-item\">
  <div className=\"handle\">
   <a href=\"javascript:;\" rel=\"external nofollow\" onClick={this.handleDeleteComment}>删除</a>
  </div>
  <p className=\"user\"><span>{comments.username}</span><span>说：</span></p>
  <p className=\"centence\">{comments.content}</p>
  </div>
 );
 }
}
 
export default CommentItem;

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持免费资源网。