socket.io client cheatsheet code example
Example 1: socket emit cheat sheet
io.on('connect', onConnect);function onConnect(socket){ // sending to the client socket.emit('hello', 'can you hear me?', 1, 2, 'abc'); // sending to all clients except sender socket.broadcast.emit('broadcast', 'hello friends!'); // sending to all clients in 'game' room except sender socket.to('game').emit('nice game', "let's play a game"); // sending to all clients in 'game1' and/or in 'game2' room, except sender socket.to('game1').to('game2').emit('nice game', "let's play a game (too)"); // sending to all clients in 'game' room, including sender io.in('game').emit('big-announcement', 'the game will start soon'); // sending to all clients in namespace 'myNamespace', including sender io.of('myNamespace').emit('bigger-announcement', 'the tournament will start soon'); // sending to a specific room in a specific namespace, including sender io.of('myNamespace').to('room').emit('event', 'message'); // sending to individual socketid (private message) io.to(socketId).emit('hey', 'I just met you'); // WARNING: `socket.to(socket.id).emit()` will NOT work, as it will send to everyone in the room // named `socket.id` but the sender. Please use the classic `socket.emit()` instead. // sending with acknowledgement socket.emit('question', 'do you think so?', function (answer) {}); // sending without compression socket.compress(false).emit('uncompressed', "that's rough"); // sending a message that might be dropped if the client is not ready to receive messages socket.volatile.emit('maybe', 'do you really need it?'); // specifying whether the data to send has binary data socket.binary(false).emit('what', 'I have no binaries!'); // sending to all clients on this node (when using multiple nodes) io.local.emit('hi', 'my lovely babies'); // sending to all connected clients io.emit('an event sent to all connected clients');};
Example 2: socket emit to specific room using nodejs socket.io
io.on('connection', socket => { socket.on('disconnecting', () => { const rooms = Object.keys(socket.rooms); // the rooms array contains at least the socket ID }); socket.on('disconnect', () => { // socket.rooms === {} });});