cocos creator中javaScript使用WebSoc

本文中使用WebSocket与服务器长连接，通信采用的是protobuf：如何在javascript环境下使用google protobuf
Packet.proto

syntax = "proto2";

message Packet {
    required int32 type = 1;
}

与服务器建立链接

      let self = this;
      // connectionProtocol(字符串协议参数 可选) 可为字符串或包含字符串的数组
      let connectionProtocol = "";
        //原生平台上使用 wss的websocket需要自己添加一个证书(浏览器或者微信小程序不需要填写此参数)
        let pemUrl = cc.url.raw("resources/cert.pem")
        let ws = new WebSocket(url, connectionProtocol, pemUrl);

        ws.onopen = function (event) {
            console.log("ws is open ");
        };
        ws.onmessage = function (event) {
            self.onMessage(event.data);
        };
        ws.onerror = function (event) {
            console.log("ws has an error ");
        };
        ws.onclose = function (event) {
            console.log("ws is closed ");
        };

向服务器发送消息

      // 向服务器发送消息
        let packet_pb = require('Packet_pb');
        let packet = new packet_pb.Packet();
        packet.setType(1);
        let msg = packet.serializeBinary();
        // 在某些平台, 如原生平台或者微信小程序, 发送的是 arrayBuffer
        // 若在浏览器平台则直接发送msg
        ws.send(msg.buffer);

接收服务器发来的消息

onMessage: function (msg) {
        if (msg.constructor != null && msg.constructor.name == "Blob") {
            //浏览器会得到一个blob对象，必须转化，否则不能解析
            //将Blob 对象转换成 ArrayBuffer
            let reader;
            if (typeof (FileReader) == "undefined") {
                reader = new FileReaderSync();
            } else {
                reader = new FileReader();
            }
            if (reader != null) {
                let self = this;
                reader.onload = function (e) {
                    self.processMessage(reader.result);
                }
                reader.readAsArrayBuffer(msg);
            }
        } else {
            //原生平台和微信小游戏上接收到的直接是: ArrayBuffer
                this.processMessage(msg, serverType);
        }
    },

    processMessage: function (msg) {
        let packet_pb = require('Packet_pb');
        let u8Msg = new Uint8Array(msg);
        let packet = packet_pb.Packet.deserializeBinary(u8Msg);
        this.enqueuePacketReceived(packet, serverType);
    },