react前端提交表单数据至后端

<form method='post'>
	   <p>id</p>
	   <input type="name" name="name" onChange={this.handleChange}/>
	   <p>password</p>
	   <input type="password" name="password" onChange={this.handleChange}/>
	   <br />
	   <button onClick={this.onSubmit}>submit</button>
</form>

 onSubmit=()=>{
    let queryStringRequest = new Request('http://localhost:3000/register', {
      method: 'post',
      body : this.state
    })
    fetch(queryStringRequest).then(res => {
          console.log(res)
    })
 }

后端代码

const express = require('express')
const bodyParser = require('body-parser');
const app = express();
const registerRouter = express.Router();
/* 为了使用req.body*/
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use((req,res,next)=>{
    console.log("有人请求服务器")
    next()
})
app.use('/register', registerRouter);

registerRouter.post("/", function (req, res) {
    console.log(req.body)
app.listen(3300,() =>{
    console.log("服务器运行在3300端口")
})