1, req. body

2, req query

3, req params

1. req. body example

body is not provided by nodejs by default and you need to load body-ES20en middleware to use ES21en.body, which is usually used to parse data in POST requests

<form action='/test' method='post'>
  <input type='text' name='name' value='lmw'>
  <input type='text' name='tel' value='1234567'>
  <input type='submit' value='Submit'>
</form>
app.post('/test', function(req, res) {
  console.log(req.body.name);
  console.log(req.body.tel);
});

2. req. query example

nodejs is available by default, without the need to load middleware, and this method is commonly used to parse data in get requests

GET /test?name=lmw&tel=123456789

app.get('/test', function(req, res) {
  console.log(req.query.name);
  console.log(req.query.tel);
});

3. req.query and req

<form action='/test?id=1' method='post'>
  <input type='text' name='name' value='lmw'>
  <input type='text' name='tel' value='123456789'>
  <input type='submit' value='Submit'>
</form>
app.post('/test', function(req, res) {
  console.log(req.query.id);
  console.log(req.body.name);
  console.log(req.body.tel);
});

4. req.params

The other way is to pass parameters to the server, but this is not a traditional standard specification, but an extension of HTTP Routing

GET /test/lmw/123456789

app.get('/test/:name/:tel', function(req, res) {
  console.log(req.params.name);
  console.log(req.params.tel);
});

Conclusion:

req.query: querystring in the parsed url, such as ? name=haha, req. query = {name: ‘haha’}

req. params: Resolves placeholders in url, such as /:name, access /haha, req. params with the value {name: ‘haha’}

req. body: after parsing the request body, you need to use the relevant module, such as ES80en-ES81en, the request body is {“name”: “haha”}, then req. body is {name: ‘haha’}