.h檔案

#import <Foundation/Foundation.h>
#import "GCDAsyncSocket.h"

@interface GCDSocketManager : NSObject

@property(nonatomic,strong) GCDAsyncSocket *socket;

//單例
+ (instancetype)sharedSocketManager;

//連線
- (void)connectToServer;

//斷開
- (void)cutOffSocket;

@end

.m檔案

#import "GCDSocketManager.h"

#define SocketHost @"地址"
#define SocketPort 埠

@interface GCDSocketManager()<GCDAsyncSocketDelegate>

//握手次數
@property(nonatomic,assign) NSInteger pushCount;

//斷開重連定時器
@property(nonatomic,strong) NSTimer *timer;

//重連次數
@property(nonatomic,assign) NSInteger reconnectCount;

@end

@implementation GCDSocketManager

//全域性訪問點
+ (instancetype)sharedSocketManager {
    static GCDSocketManager *_instance = nil;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        _instance = [[self alloc] init];
    });
    return _instance;
}

//可以在這裡做一些初始化操作
- (instancetype)init
{
    self = [super init];
    if (self) {
        
    }
    return self;
}

#pragma mark 請求連線
//連線
- (void)connectToServer {
    self.pushCount = 0;
    
    self.socket = [[GCDAsyncSocket alloc] initWithDelegate:self delegateQueue:dispatch_get_main_queue()];
    
    NSError *error = nil;
    [self.socket connectToHost:SocketHost onPort:SocketPort error:&error];
    
    if (error) {
        DLog(@"SocketConnectError:%@",error);
    }
}

#pragma mark 連線成功
//連線成功的回撥
- (void)socket:(GCDAsyncSocket *)sock didConnectToHost:(NSString *)host port:(uint16_t)port {
    DLog(@"socket連線成功");
    [self sendDataToServer];
}

//連線成功後向伺服器傳送資料
- (void)sendDataToServer {
    //傳送資料程式碼省略...
    
    //傳送
    [self.socket writeData:jsonData withTimeout:-1 tag:1];
    
    //讀取資料
    [self.socket readDataWithTimeout:-1 tag:200];
}

//連線成功向伺服器傳送資料後,伺服器會有響應
- (void)socket:(GCDAsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag {
    
    [self.socket readDataWithTimeout:-1 tag:200];
    
    //伺服器推送次數
    self.pushCount++;
    
   //在這裡進行校驗操作,情況分為成功和失敗兩種,成功的操作一般都是拉取資料
}

#pragma mark 連線失敗
//連線失敗的回撥
- (void)socketDidDisconnect:(GCDAsyncSocket *)sock withError:(NSError *)err {
    DLog(@"Socket連線失敗");
    
    self.pushCount = 0;
    
    NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
    
    NSString *currentStatu = [userDefaults valueForKey:@"Statu"];
    
    //程式在前臺才進行重連
    if ([currentStatu isEqualToString:@"foreground"]) {
        
        //重連次數
        self.reconnectCount++;
        
        //如果連線失敗 累加1秒重新連線 減少伺服器壓力
        NSTimer *timer = [NSTimer scheduledTimerWithTimeInterval:1.0 * self.reconnectCount target:self selector:@selector(reconnectServer) userInfo:nil repeats:NO];
        
        self.timer = timer;
    }
}

//如果連線失敗,5秒後重新連線
- (void)reconnectServer {
    
    self.pushCount = 0;
    
    self.reconnectCount = 0;
    
    //連線失敗重新連線
    NSError *error = nil;
    [self.socket connectToHost:SocketHost onPort:SocketPort error:&error];
    if (error) {
        DLog(@"SocektConnectError:%@",error);
    }
}

#pragma mark 斷開連線
//切斷連線
- (void)cutOffSocket {
    DLog(@"socket斷開連線");
    
    self.pushCount = 0;
    
    self.reconnectCount = 0;
    
    [self.timer invalidate];
    self.timer = nil;
    
    [self.socket disconnect];
}
@end