node. js common methods to obtain parameters of summary

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'}