前端实现websocket类封装

随着Web应用程序的发展，越来越多的人开始利用Websocket技术来构建实时应用程序。Websocket是一种在客户端和服务器之间建立持久连接的协议。这种协议可以在一个单独的连接上实现双向通信。与HTTP请求-响应模型不同，Websocket允许服务器自主地向客户端发送数据。这种实时连接的能力使得Websocket在许多应用场景中得到了广泛的应用。

Websocket技术的优点之一是减少了网络延迟。在传统的HTTP请求-响应模型中，客户端必须不断地向服务器发送请求以获取更新的数据。这种不断的请求-响应循环会占用大量的带宽和处理能力。而Websocket的持久连接可以在服务器有新数据时立即向客户端发送，从而减少了网络延迟和服务器负载。

另一个优点是Websocket可以处理大量的并发连接。在传统的HTTP请求-响应模型中，每个请求都必须在服务器上进行处理，这可能会对服务器造成负载压力。但是，Websocket的持久连接可以在服务器上保持打开状态，从而减少了与每个连接相关的开销。这使得服务器可以处理大量的并发连接而不会降低性能。

Websocket还可以用于实时通信。例如，聊天应用程序可以使用Websocket来实现实时消息传递。在这种情况下，Websocket的持久连接可以在服务器上保持打开状态，以便客户端可以接收实时消息。这种实时通信的能力使得Websocket在许多应用程序中得到了广泛的应用。

总之，Websocket技术在现代Web应用程序中发挥着越来越重要的作用。它可以减少网络延迟和服务器负载，处理大量的并发连接，并提供实时通信能力。因此，如果您正在构建一个需要实时更新的Web应用程序，那么Websocket技术可能是您的理想选择。

封装类实现

import { WebSocketConfigOption } from './WebSocketConfigOption';export class ReconnectableWebSocket {private ws!: WebSocket; // ws实例private opt: WebSocketConfigOption; // ws配置项private lockReconnect: boolean = false; // 避免ws重复连接private isClosingWindow: boolean = false;private reconnectTimeout: any;private heartSendInterval: any;constructor(option: WebSocketConfigOption) {if (null === option.url || '' === option.url) {throw ('url不能为空');}this.opt = option;this.initWebSocket();}private initWebSocket() {if (null == this.opt.secWebSocketProtocol) {this.ws = new WebSocket(this.opt.url);} else if (this.opt.secWebSocketProtocol.length == 0) {this.ws = new WebSocket(this.opt.url);} else {this.ws = new WebSocket(this.opt.url, this.opt.secWebSocketProtocol);}this.initEventHandle();window.onbeforeunload = () => {this.isClosingWindow = true;this.ws.close(); // 当窗口关闭时，主动去关闭websocket连接。}}private initEventHandle() {this.ws.onclose = () => {console.log('ws连接关闭!' + this.opt.url);this.opt.onclose && this.opt.onclose();this.heartCheckStop();if (!this.isClosingWindow) {this.reconnect();}}this.ws.onerror = () => {console.log('ws连接错误!' + this.opt.url);this.opt.onerror && this.opt.onerror();this.heartCheckStop();if (!this.isClosingWindow) {this.reconnect();}}this.ws.onopen = () => {console.log('ws连接成功!' + this.opt.url);this.opt.onopen && this.opt.onopen();this.heartCheckStart();}this.ws.onmessage = (event: any) => {this.opt.onmessage && this.opt.onmessage(event);}}/** 重连 */private reconnect() {if (this.lockReconnect) {return;}this.lockReconnect = true;this.reconnectTimeout = setTimeout(() => {this.initWebSocket();this.lockReconnect = false;}, 2000);}/** 关闭重连 */private reconnectStop(): void {clearTimeout(this.reconnectTimeout);}/** 开启心跳包保持连接 */private heartCheckStart(): void {this.ws.send('heartCheck');this.heartSendInterval = setInterval(() => {this.ws.send('heartCheck');}, 5 * 60 * 1000);}/** 关闭心跳包 */private heartCheckStop(): void {clearInterval(this.heartSendInterval);}/** 主动关闭连接 */public close(): void {this.reconnectStop();this.heartCheckStop();this.isClosingWindow = true;this.ws.close();}}

配置类实现

export type WebSocketConfigOption = {url: string;secWebSocketProtocol?: Array<string>;onopen?: () => void;onmessage?: (msg: any) => void;onerror?: () => void;onclose?: () => void;}

应用示例

import { WebSocketConfigOption } from '../websocket/WebSocketConfigOption';
import { ReconnectableWebSocket } from '../websocket/ReconnectableWebSocket';
import { InnerMqService } from '../../rx/inner-mq.service';export class MapMessageConnection {private ws!: ReconnectableWebSocket;constructor(private path: string,private innerMqService: InnerMqService,) {this.connection();}/** 连接 */private connection(): void {let wsConfig: WebSocketConfigOption = {url: this.path,onopen: () => {},onerror: () => {},onmessage: (msg: any) => {if (msg.data && msg.data !== '') {let data = JSON.parse(msg.data);this.innerMqService.pub(data.title, data.content);}}}this.ws = new ReconnectableWebSocket(wsConfig);}/** 断开连接 */public disConnection(): void {this.ws.close();}}

import { InnerMqClient } from '../../rx/inner-mq.service';
import { SubmitService } from '../../service/submit.service';
import { MapBase } from '../../map/map-base';
import { CommonUtil } from '../../util/common-util';
import { MapPage } from '../../view/page/map/map.page';
import { MapDraw } from '../../map/draw/map-draw';
import { MapWrap } from '../../map/draw/map-wrap';
import { GeoUtil } from "../../map/geo-util";
import { Point } from "../../map/entity/Point";export class MapMessageProcessor {constructor(private mqClient: InnerMqClient,private submitService: SubmitService,private mapBase: MapBase,private mapPage: MapPage,) {/** 放大 */mqClient.sub('ZoomIn').subscribe((res) => {mapBase.zoomIn();});/** 缩小 */mqClient.sub('ZoomOut').subscribe((res) => {mapBase.zoomOut();});/** 拖动 */mqClient.sub('Pan').subscribe((res) => {mapBase.pan();});/** 显示网格 */mqClient.sub('GridSwitch').subscribe((res) => {let update;if (mapBase.getGridVisible()) {mapBase.closeGrid();update = false;} else {mapBase.showGrid();update = true;}let config = mapBase.getMapConfig();if (config) {config.grid = update;CommonUtil.setConfigCache(config);mapBase.setMapConfig(config);}});/** 切换图层源 */mqClient.sub('SwitchResource').subscribe((res) => {// 切换图层debuggerlet lastType = mapBase.getCurrentCoordinateType();mapBase.switchMapResource(res);let currentType = mapBase.getCurrentCoordinateType();// 保存设置let config = mapBase.getMapConfig();if (config) {config.layer = res;CommonUtil.setConfigCache(config);mapBase.setMapConfig(config);}// 检查坐标类型if (lastType != currentType) {if (lastType == 'wgs84' && currentType == 'gcj02') {mapBase.turnMapFeaturesFromWgs84ToGcj02();} else if (lastType == 'gcj02' && currentType == 'wgs84') {mapBase.turnMapFeaturesFromGcj02ToWgs84();}}// 回调setTimeout(() => {mapPage.updateShowInfo();});});/** 绘制类型切换 - */mqClient.sub('SwitchDrawType').subscribe((res) => {mapBase.setDrawType(res);});/** 绘制 - */mqClient.sub('OpenDraw').subscribe((res) => {mapBase.pan();mapBase.removeDrawedFeatures();mapBase.openDraw({drawEnd: () => {setTimeout(() => {mapBase.removeDrawInteraction();})},modifyEnd: () => {}});});/** 绘制指定多边形并定位 - */mqClient.sub('DrawPolygonAndPositioning').subscribe((res) => {mapBase.pan();mapBase.removeDrawedFeatures();let blocks = JSON.parse(res);for (let i = 0; i < blocks.length; i++) {let points: Array<Point> = [];for (let j = 0; j < blocks[i].length; j++) {let point = new Point(blocks[i][j].lng, blocks[i][j].lat);if (mapBase.getCurrentCoordinateType() == 'wgs84') {points.push(GeoUtil.gcj02_To_wgs84(point));} else {points.push(point);}}let feature = MapDraw.createPolygonFeature(points);MapWrap.addFeature(mapBase, mapBase.drawLayerName, feature);}mapBase.setFitviewFromDrawLayer();});/** fitview - */mqClient.sub('Fitview').subscribe((res) => {mapBase.setFitviewFromDrawLayer();});/** 删除绘制 - */mqClient.sub('RemoveDrawedShape').subscribe((res) => {mapBase.removeDrawedFeatures();});/** 提交区块下载 - */mqClient.sub('SubmitBlockDownload').subscribe((res) => {let data = {tileName: this.mapBase?.getCurrentXyzName(),mapType: CommonUtil.getMapType(this.mapBase?.getCurrentXyzName()),tileUrl: this.mapBase?.getCurrentXyzUrlResources(),points: this.mapBase?.getDrawedPoints(),};this.submitService.blockDownload(data).then((r) => {});});/** 提交世界下载 - */mqClient.sub('SubmitWorldDownload').subscribe((res) => {let data = {tileName: this.mapBase?.getCurrentXyzName(),mapType: CommonUtil.getMapType(this.mapBase?.getCurrentXyzName()),tileUrl: this.mapBase?.getCurrentXyzUrlResources()};this.submitService.worldDownload(data).then((r) => {});});}}