how do node and socket.io take the initiative to send messages to the front end
I use node to read data from the database, and send new data directly to the front end. Because the database is sometimes updated several times in a minute, node reads it and sends it out.
the foreground user can just leave the page open
now users have to send an event to the backend
how to solve
Thank you
have you finished reading the document? https://socket.io/get-started. uses broadcast (Broadcasting).
Direct io.emit is sent to all clients connected to the default namespace
io.on('connection', function (socket) {
socket.emit('event', function (data, callback) {
//event
})
socket.broadcast.emit('event', function (data, callback) {
//event
})
io.emit('event', function (data, callback) {
//event
})
io.to(sockedID).emit('event', function (data, callback) {
//event
})
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