Question

我正在尝试将通用详细信息数据从我的反应前端传递到我的节点服务器。我目前收到连接被拒绝的错误。

（选项http://localhost:5000/api/home net :: ERR_CONNECTION_REFUSED）。

这是我的onSubmitForm函数：

  onSubmitForm(e){
  e.preventDefault();

  let data = {
            generalDetail: this.state.generalDetails,
            firstName: this.state.firstName,
            middleName: this.state.middleName,
            lastName: this.state.lastName
      };

      axios.post("http://localhost:5000/home", data).then(() => {

       }).catch(() => {
          console.log("Something went wrong. Plase try again later");
      });


}
  //end

  onContentChange(fieldname, data){

    console.log('On Content Change', data);

     this.setState({
       [fieldname]: data

    });
  }



}

这是我的server.js文件

const express = require('express');

const app = express();


// http://localhost:5000/api/home

app.post('/api/home', (req, res) => {
  const data = [
    {req.body.generalDetail},
  ];

  res.json(data);
});

const port = 5000;

app.listen(port, () => `Server running on port ${port}`);

Answer 1

尝试

const express = require('express')
const app = express()
const port = 8000 //your port number

const cors = require('cors')
app.use(cors())
var bodyParser = require('body-parser')
app.use( bodyParser.json() );       // to support JSON-encoded bodies
app.use(bodyParser.urlencoded({     // to support URL-encoded bodies
  extended: true
}));

Answer 2

您可以将代码更改为此

示例

onSubmitForm = e => {
        e.preventDefault();
        let data = {
              generalDetail: this.state.generalDetails,
              firstName: this.state.firstName,
              middleName: this.state.middleName,
              lastName: this.state.lastName
        };

        axios.post("http://localhost:5000/api/home", data).then(() => {
           //do something
         }).catch(() => {
            console.log("Something went wrong. Plase try again later");
        });
    }

Answer 3

尝试在后端代码（server.js）中添加cors预检代码。

app.use(function (req, res, next) {
  res.header("Access-Control-Allow-Origin", req.headers.origin);
  res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, Authorization");
  res.header("Access-Control-Allow-Methods", "POST, GET, PUT, OPTIONS");
  res.header("Access-Control-Allow-Credentials", true);
  next();
});
app.post('/api/home', (req, res) => {
  const data = [{ generalDetails: req.body.generalDetail }];
  res.json(data);
});

将数据从React传递到节点快递服务器

3 个答案: