javascript tutorial - [Solved-5 Solutions] POST query parameters - javascript - java script - javascript array
Problem:
How to retrieve POST query parameters ?
Solution 1:
Things have changed again in Express 4.0:
$ npm install --save body-parser
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and then:
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
}));
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The rest is like in Express 3.0:
- Firstly we need to add some middleware to parse the post data of the body.
- Add one or both of the following lines of code:
app.use(express.json()); // to support JSON-encoded bodies
app.use(express.urlencoded()); // to support URL-encoded bodies
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Then, in our handler, use the req.body object:
// assuming POST: name=foo&color=red <-- URL encoding
//
// or POST: {"name":"foo","color":"red"} <-- JSON encoding
app.post('/test-page', function(req, res) {
var name = req.body.name,
color = req.body.color;
// ...
});
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Note that the use of express.bodyParser() is not recommended.
app.use(express.bodyParser());
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...is equivalent to:
app.use(express.json());
app.use(express.urlencoded());
app.use(express.multipart());
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Security concerns exist with express.multipart(), and so it is better to explicitly add support for the specific encoding type(s) we require. If we do need multipart encoding (to support uploading files for example) then we should read this https://groups.google.com/forum/.
Solution 2:
This will do it if we want to build the posted query without middleware:
app.post("/register/",function(req,res){
var bodyStr = '';
req.on("data",function(chunk){
bodyStr += chunk.toString();
});
req.on("end",function(){
res.send(bodyStr);
});
});
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That will send this to the browser
email=emailval&password1=pass1val&password2=pass2val
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It's probably better to use middleware though so we don't have to write this over and over in each route.
Solution 3:
Note for Express 4 users:
If we try and put app.use(express.bodyParser()); into our app, you'll get the following error when we try to start our Express server:
Error: Most middleware (like bodyParser) is no longer bundled with Express and must be installed separately. Please see https://github.com/senchalabs/connect#middleware .
You'll have to install the package body-parser separately from npm , then use something like the following:
var express = require('express');
var bodyParser = require('body-parser');
var app = express();
app.use(bodyParser());
app.use(function (req, res, next) {
console.log(req.body) // populated!
next();
})
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Solution 4:
Given some form:
<form action='/somepath' method='post'>
<input type='text' name='name'></input>
</form>
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Using express
app.post('/somepath', function(req, res) {
console.log(JSON.stringify(req.body));
console.log('req.body.name', req.body['name']);
});
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Output:
{"name":"x","description":"x"}
req.param.name x
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Solution 5:
app.use(express.bodyParser());
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Then for app.post request we can get post values via req.body.{post request variable}.