Socket.io how to send JavaScript object

javascript json node.js socket.io
zsd picture zsd · Aug 4, 2012 · Viewed 72.4k times · Source

How to send JavaScript Object with Socket.io from server to client? I'm using Socket.io as WebSocket(sending with .send() and listen with message event). When I'm trying to do something like on server-side:

var myObject = {
    message: 'Hello World!'
}

socket.send(myObject);

on client-side I'm getting only this String: [object Object]

Answer

Brad picture Brad · Aug 4, 2012

You actually need to emit an event instead:

 socket.emit('yourEvent', myObject);

If you use .send(), you are simply sending the string representation of your object, which is where the problem is occurring. Note that you can use .send(), but you would have to JSON-encode the object first, and decode it on reception.

Unless you have a specific reason, it's best to use the standard Socket.IO .emit() method, as it does all of this for you. That's what it is there for.

Related questions

node.js TypeError: path must be absolute or specify root to res.sendFile [failed to parse JSON]

[add] So my next problem is that when i try adding a new dependence (npm install --save socket.io). The JSON file is also valid. I get this error: Failed to parse json npm ERR! Unexpected string npm ERR! File: /…

Read More
How to parse JSON using Node.js?

How should I parse JSON using Node.js? Is there some module which will validate and parse JSON securely?

Read More
How can I print a circular structure in a JSON-like format?

I have a big object I want to convert to JSON and send. However it has circular structure. I want to toss whatever circular references exist and send whatever can be stringified. How do I do that? Thanks. var obj = { …

Read More