javascript - Node.js, Socket.io emit not working -

i making website in socket.io. emit method not working in code. can't see errors in code. here server code.

var io = require("socket.io").listen(server);  //some external codes running server in node.js  io.on("connection", function(socket) {     //this line working.     console.log("socket connected.");      io.on("requestnewmap", function(data) {         //create new map object in here.         io.emit("responsenewmap", { mapdata: map });     }); }); 

and client side javascript code.

var socket = io();  socket.on("responsenewmap", function(data) {     var map = data.mapdata;      //draw map in canvas's context. });  //setinterval runs method every 2 seconds. function requestnewmap() {     socket.emit("requestnewmap"); } 

this part wrong:

io.on("requestnewmap", function(data) {     //create new map object in here.     io.emit("responsenewmap", { mapdata: map }); }); 

i use socket there in:

socket.on("requestnewmap", function(data) {     //create new map object in here.     socket.emit("responsenewmap", { mapdata: map }); }); 

i think io.emit should work fine, send response every connected client, io.on('requestnewmap',...) won't work since requestnewmap not io standard event.