Handle POST Form Data with Express JS

Express doesn't handle FormData instances by default. FormData is useful for tasks like uploading a file. You need to use a separate FormData parser, like Formidable, as shown below.

const formidable = require('formidable'); app.post('/upload', function(req, res) { const form = new formidable.IncomingForm(); // Parse `req` and upload all associated files. `files` contains // all files that were uploaded with the form. form.parse(req, function(err, fields, files) { if (err) { return res.status(400).json({ error: err.message }); } const [firstFileName] = Object.keys(files); res.json({ filename: firstFileName }); }); });

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Espresso supports:

• Route handlers, like `app.get()` and `app.post()`
• Express-compatible middleware, like `app.use(require('cors')())`
• Express 4.0 style subrouters

As a bonus, Espresso also supports async functions, unlike Express.

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More Express Tutorials

• How to Set Response Headers in Express
• What Does `app.use(express.json())` Do in Express?
• Handling POST Requests with Express
• What Does `app.use(express.static())` Do in Express?
• The `app.get()` Function in Express
• The `app.use()` Function in Express
• Express Template Engines