SignalR

一、百度可知：ASP.NET SignalR 是为 ASP.NET 开发人员提供的一个库，可以简化开发人员将实时 Web 功能添加到应用程序的过程。实时 Web 功能是指这样一种功能：当所连接的客户端变得可用时服务器代码可以立即向其推送内容，而不是让服务器等待客户端请求新的数据。
二、现在我们在iOS客户端利用SignalR建立长连接。开源库

1. pod 'SwiftSignalRClient'

2.在OC项目中新建swift文件，创建桥接文件，然后在项目中

#import "TestDemo-Swift.h"//TestDemo为项目名称

3.因为SwiftSignalRClient没有做OC的支持，所以这里封装一层来支持OC

import Foundation
import SwiftSignalRClient
//SignalR的返回值都需要遵守codeble协议，不能用Any、AnyObject，所以这里声明一个结构体接收
struct ParamData:Codable {
       var Id: String?
       var UserId: Int?
       var NiceName: String?
       var Time: Int?
       var DataType: String?
       var JsonData: String?
       var OrganizationCode: String?
       var CustomerId: Int?
}

@objc public protocol XFSignalRClientDelegate : class {

    func clientDidConnectSuccess(client: XFSignalRClient)

    func clientDidConnectFailed(client: XFSignalRClient, error: Error)

    func clientDidClosed(client: XFSignalRClient, error: Error?)
}
@objcMembers public class XFSignalRClient : NSObject {
    

    var url: String?
    var headers: [String: String]?
    var PlatUserId: [String: Int]?
    private var connection: HubConnection?
    public weak var delegate: XFSignalRClientDelegate?
    private override init() {
        super.init()
    }

    static let swiftSharedInstance = XFSignalRClient()//写一个管理单例
        //在oc中这样写才能被调用
        @objc open class func sharedInstance() -> XFSignalRClient
        {
            return swiftSharedInstance
        }
   
    public func start() {

        if (self.connection != nil) {
            return
        }

        self.connection = HubConnectionBuilder(url: URL(string: self.url!)!)
        
            .withAutoReconnect()//添加了自动重连
            .withLogging(minLogLevel: .debug)
            .withHttpConnectionOptions(configureHttpOptions: { (httpConnectionOptions) in


                if let header = self.headers {
                    for (key, value) in header {

                        httpConnectionOptions.headers[key] = value

                    }

                }

            })
            .build()

        self.connection?.delegate = self


    }

    public func stop() {
        if (self.connection == nil) {
            return
        }
        self.connection?.stop()
    }
//注册服务器方法，在block中接收数据
    public func on(method: String, callback: @escaping (_ meg: XFSignalRModel?) -> Void) {
        self.connection?.on(method: method, callback: { (argumentExtractor) in
            let data = try argumentExtractor .getArgument(type: ParamData.self);
            let model:XFSignalRModel = XFSignalRModel()
            model.UserId = String(data.UserId!)
            model.JsonData = data.JsonData
            model.DataType = data.DataType
            model.Id = data.Id
            callback(model)//这里的model是另外写了一个遵循codable协议的类，在OC中调用
            

        })

        self.connection?.start()//注册服务器方法后才能start()，不然无法收到数据
        
    }

    //添加到组的方法，连接成功后，需要添加到组才能接收到数据
    public func invoke(method: String, invocationDidComplete: @escaping (_ error: Error?) -> Void) {
        //具体参数和服务端协商
        self.connection?.invoke(method: method, arguments: [self.PlatUserId], invocationDidComplete: invocationDidComplete)
     }
    
    
}

    
extension XFSignalRClient: HubConnectionDelegate {
    public func connectionDidOpen(hubConnection: HubConnection) {
        self.delegate?.clientDidConnectSuccess(client: self)
    }
    

    public func connectionDidFailToOpen(error: Error) {
        self.delegate?.clientDidConnectFailed(client: self, error: error)

    }


    public func connectionDidClose(error: Error?) {

        self.delegate?.clientDidClosed(client: self, error: error)

    }
    
    public func connectionWillReconnect(error: Error) {
        print("开始重新连接")
        
    }
    
    public func connectionDidReconnect() {
        print("重连成功")
        self.delegate?.clientDidConnectSuccess(client: self) //重新连接后需要重新加入组才能收到消息
    }
}

4.OC中调用

    NSString *pushUrl = @"http://xxxxxx;
    int GuardianId = 32323;
    NSDictionary *paramDic = @{@"PlatUserId":@(GuardianId)};
    [XFSignalRClient swiftSharedInstance].url = pushUrl;
    [XFSignalRClient swiftSharedInstance].PlatUserId = paramDic;
    [XFSignalRClient swiftSharedInstance].delegate = self;
    [[XFSignalRClient swiftSharedInstance] start];
    
    [[XFSignalRClient swiftSharedInstance] onMethod:@"ReciveSaasMessage" callback:^(XFSignalRModel * _Nullable model) {
        
        //处理数据
        
    }];

在连接成功的代理中调用加入组的方法

- (void)clientDidConnectSuccessWithClient:(XFSignalRClient *)client {
    [client invokeWithMethod:@"AddToGroup" invocationDidComplete:^(NSError * _Nullable error) {
        if (error) {
            NSLog(@"error %@",error);
        }
    }];
}

好了，这样就可以接收数据了。要是有什么不对的地方欢迎指正。
参考博客https://www.jianshu.com/p/8c9d18511df2