>我有一个redux表单，用于从用户接收数据并将其发布到后端API服务器。在将数据发布到服务器时，我想为发布到服务器的每组数据生成一个唯一的 id，以便以后可以使用该 id 引用该特定集并将其显示给用户。那么，如何在将一组数据发布到服务器的同时自动生成该唯一ID？
我的redux 表单的代码如下所示：
import React, { Component } from 'react';
import { Field, reduxForm } from 'redux-form';
import { Link } from 'react-router-dom';
import { connect } from 'react-redux';
import { createPosts } from '../actions/posts_action';
class CreatePost extends Component {
constructor() {
super();
this.state = {
selectValue : ''
};
this.handleChange = this.handleChange.bind(this);
this.renderCategory = this.renderCategory.bind(this);
}
renderField(field) {
return(
<div className="title-design">
<label className="label-design"> {field.label} </label>
<input
type="text"
className="title-input"
{...field.input}
/>
<div className="text-help has-danger">
{field.meta.touched ? field.meta.error : ''}
</div>
</div>
);
}
handleChange(e) {
const value=e.target.value;
this.props.change("categories",value);
this.setState({selectValue: value}, () => {
console.log(value)
});
}
renderCategory(field) {
return(
<div className="title-design">
<label className="label-design">{field.label} </label>
<Field name="category" className="title-input" component="select">
<option></option>
<option value="react">React</option>
<option value="redux">Redux</option>
<option value="udacity">Udacity</option>
</Field>
<div className="text-help has-danger">
{field.meta.touched ? field.meta.error : ''}
</div>
</div>
);
}
onSubmit(values) {
this.props.createPosts(values, () => {
this.props.history.push('/');
});
}
render() {
const { handleSubmit } = this.props;
return (
<form onSubmit={handleSubmit(this.onSubmit.bind(this))}>
<Field
label="Title for Post"
name="title"
component={this.renderField}
/>
<Field
label="Post Content"
name="body"
component={this.renderField}
/>
<Field
label="Category"
name="category"
component={this.renderCategory}
/>
<button type="submit" className="btn btn-primary">Submit</button>
<Link to="/">
<button className="cancel-button">Cancel</button>
</Link>
</form>
);
}
}
function validate(values) {
const errors = {} ;
if (!values.title) {
errors.title = "Enter a title";
}
if (!values.body) {
errors.body = "Enter some content";
}
if(!values.category) {
errors.category = "Please select a category";
}
if (!values.id) {
errors.id = "ID not generated";
}
return errors;
}
export default reduxForm({
validate : validate, //validate
form : 'CreatePostForm'
})(
connect(null,{ createPosts })(CreatePost)
);
创建新帖子的操作创建者如下：
//Action Creator for creating posts
export function createPosts(values, callback) {
return dispatch => {
return axios.post(`${API}/posts`,values,{headers})
.then((data) => {
callback();
console.log(data)
dispatch({
type: CREATE_POST,
payload: data
})
})
}
}
用于创建帖子的化简器：
import _ from 'lodash';
import { FETCH_POSTS, FETCH_POST, CREATE_POST } from '../actions/posts_action';
export default function(state = {}, action) {
switch (action.type) {
case FETCH_POST:
// const post = action.payload.data;
// const newState = { ...state, };
// newState[post.id] = post;
// return newState;
return {...state, [action.payload.id]: action.payload};
case FETCH_POSTS:
return {posts: { ...state.posts, ...action.payload }};
case CREATE_POST:
return {posts: { ...state, ...action.payload}};
default:
return state;
}
}
那么，如何为发送到服务器的每组数据生成id呢？
编辑 1：
我正在尝试在我的onSubmit()方法上添加uuid，如下所示，但它不起作用。我坐着不是应该怎么做，还是我必须以其他方式做？
onSubmit(values) {
this.props.createPosts(values, () => {
uuidv1();
this.props.history.push('/');
});
}
编辑 2：
帖子的服务器文件：
const clone = require('clone')
let db = {}
const defaultData = {
"8xf0y6ziyjabvozdd253nd": {
id: '8xf0y6ziyjabvozdd253nd',
timestamp: 1467166872634,
title: 'Udacity is the best place to learn React',
body: 'Everyone says so after all.',
author: 'thingtwo',
category: 'react',
voteScore: 6,
deleted: false,
commentCount: 2
},
"6ni6ok3ym7mf1p33lnez": {
id: '6ni6ok3ym7mf1p33lnez',
timestamp: 1468479767190,
title: 'Learn Redux in 10 minutes!',
body: 'Just kidding. It takes more than 10 minutes to learn technology.',
author: 'thingone',
category: 'redux',
voteScore: -5,
deleted: false,
commentCount: 0
}
}
function getData (token) {
let data = db[token]
if (data == null) {
data = db[token] = clone(defaultData)
}
return data
}
function getByCategory (token, category) {
return new Promise((res) => {
let posts = getData(token)
let keys = Object.keys(posts)
let filtered_keys = keys.filter(key => posts[key].category === category && !posts[key].deleted)
res(filtered_keys.map(key => posts[key]))
})
}
function get (token, id) {
return new Promise((res) => {
const posts = getData(token)
res(
posts[id].deleted
? {}
: posts[id]
)
})
}
function getAll (token) {
return new Promise((res) => {
const posts = getData(token)
let keys = Object.keys(posts)
let filtered_keys = keys.filter(key => !posts[key].deleted)
res(filtered_keys.map(key => posts[key]))
})
}
function add (token, post) {
return new Promise((res) => {
let posts = getData(token)
posts[post.id] = {
id: post.id,
timestamp: post.timestamp,
title: post.title,
body: post.body,
author: post.author,
category: post.category,
voteScore: 1,
deleted: false,
commentCount: 0
}
res(posts[post.id])
})
}
function vote (token, id, option) {
return new Promise((res) => {
let posts = getData(token)
post = posts[id]
switch(option) {
case "upVote":
post.voteScore = post.voteScore + 1
break
case "downVote":
post.voteScore = post.voteScore - 1
break
default:
console.log(`posts.vote received incorrect parameter: ${option}`)
}
res(post)
})
}
function disable (token, id) {
return new Promise((res) => {
let posts = getData(token)
posts[id].deleted = true
res(posts[id])
})
}
function edit (token, id, post) {
return new Promise((res) => {
let posts = getData(token)
for (prop in post) {
posts[id][prop] = post[prop]
}
res(posts[id])
})
}
function incrementCommentCounter(token, id, count) {
const data = getData(token)
if (data[id]) {
data[id].commentCount += count
}
}
module.exports = {
get,
getAll,
getByCategory,
add,
vote,
disable,
edit,
getAll,
incrementCommentCounter
}
好吧，通常你会让服务器生成该 ID，然后将其作为 axios 调用响应的一部分发送回去，但如果你真的想在客户端上生成一个 ID，我建议使用 uuid 和它的各种 UUID 生成器之一： https://www.npmjs.com/package/uuid
文档中的示例：
const uuidv4 = require('uuid/v4');
uuidv4(); // -> '110ec58a-a0f2-4ac4-8393-c866d813b8d1'
你已经添加了更多的代码，我认为在你的服务器上使用uuidv4()更好;像这样：
function add (token, post) {
return new Promise((res) => {
let posts = getData(token)
let id = uuidv4();
posts[id] = {
id: id,
timestamp: post.timestamp,
title: post.title,
body: post.body,
author: post.author,
category: post.category,
voteScore: 1,
deleted: false,
commentCount: 0
}
res(posts[id])
})
}
这样，id就会在服务器上生成。 客户端不再需要依赖 uuid，并且您不"信任"客户端生成有效 ID。 id 将作为响应的一部分呈现回客户端，然后您可以在执行编辑等时从客户端使用它。