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javascriptnode.jspostexpress

How to access POST form fields in Express


Here is my simple form:

<form id="loginformA" action="userlogin" method="post">
    <div>
        <label for="email">Email: </label>
        <input type="text" id="email" name="email"></input>
    </div>
<input type="submit" value="Submit"></input>
</form>

Here is my Express.js/Node.js code:

app.post('/userlogin', function(sReq, sRes){    
    var email = sReq.query.email.;   
}

I tried sReq.query.email or sReq.query['email'] or sReq.params['email'], etc. None of them work. They all return undefined.

When I change to a Get call, it works, so .. any idea?


Solution

  • Things have changed once again starting Express 4.16.0, you can now use express.json() and express.urlencoded() just like in Express 3.0.

    This was different starting Express 4.0 to 4.15:

    $ npm install --save body-parser
    

    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
    })); 
    

    The rest is like in Express 3.0:

    Firstly you 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
    

    Then, in your 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;
        // ...
    });
    

    Note that the use of express.bodyParser() is not recommended.

    app.use(express.bodyParser());
    

    ...is equivalent to:

    app.use(express.json());
    app.use(express.urlencoded());
    app.use(express.multipart());
    

    Security concerns exist with express.multipart(), and so it is better to explicitly add support for the specific encoding type(s) you require. If you do need multipart encoding (to support uploading files for example) then you should read this.