iOS AsyncSocket使用教程

• 使用AsyncSocket的时候可以做一层封装，根据需求提供几个接口出来。比如：连接、断开连接、发送消息等等。还有接受消息，接受到的消息可以通过通知、代理、block等传出去。
• 对AsyncSocket使用.一般来说，一个用户只需要建立一个socket长连接，所以可以用单例类方便使用。

使用AsyncSocket

1.创建socket的单例类

//在LGSocketServe.h 
#import 
#import "AsyncSocket.h"
#import "GCDAsyncSocket.h"
@interface LGSocketServe : NSObject
//创建属性 用于连接
@property (nonatomic, strong, readonly) GCDAsyncSocket          *socket;
@property (nonatomic, copy,   readonly) NSString                *socketHost;
@property (nonatomic, assign, readonly) uint16_t                socketPort;

//创建单列类
+(instancetype)shareSocket;
@end



//在LGSocketServe.m
#import "LGSocketServe.h"
#import 

@interface LGSocketServe ()

@property (nonatomic, strong, readwrite) GCDAsyncSocket         *socket;
@property (nonatomic, copy,   readwrite) NSString               *socketHost;
@property (nonatomic, assign, readwrite) uint16_t               socketPort;

@end

@implementation LGSocketServe 

+(instancetype)shareSocket
{
    static dispatch_once_t onceToken;
    static LGSocketServe *socket;
    dispatch_once(&onceToken, ^{
        socket = [[LGSocketServe alloc]init];
    });
    return socket;
}
- (instancetype)init
{
    self = [super init];
    if (self) {
        self.socket = [[GCDAsyncSocket alloc]initWithDelegate:self delegateQueue:dispatch_get_global_queue(0, 0)];
    }
    return self;
}

//创建连接
- (void)connected:(NSString *)host onPort:(uint16_t)port error:(NSError *)error{
    self.socketHost = host;
    self.socketPort = port;
    //必须确认在断开连接的情况下，进行连接
    if (self.socket.isDisconnected) {
        [self.socket connectToHost:self.socketHost onPort:self.socketPort error:nil];
    }else{
        [self.socket disconnect];
        [self.socket connectToHost:self.socketHost onPort:self.socketPort error:nil];
    }
    [self.socket connectToHost:host onPort:port error:nil];
}
//心跳连接
-(void)longConnectToSocket{
    // 根据服务器要求发送固定格式的数据，假设为指令@"longConnect"，但是一般不会是这么简单的指令
    NSString *longConnect = @"longConnect\r\n";
    NSData   *dataStream  = [longConnect dataUsingEncoding:NSUTF8StringEncoding];
    [self.socket writeData:dataStream withTimeout:-1 tag:0];
}
//连接成功
- (void)socket:(GCDAsyncSocket *)sock didConnectToHost:(NSString *)host port:(uint16_t)port
{
    //每隔特定时间向服务器发送心跳包
    //在longConnectToSocket方法中进行长连接需要向服务器发送特定信息
    self.longConnectTimer
    = [NSTimer timerWithTimeInterval:kSocketConnectTimerTimeInterval
                              target:self
                            selector:@selector(longConnectToSocket)
                            userInfo:nil
                             repeats:YES];
    [[NSRunLoop currentRunLoop] addTimer:self.longConnectTimer
                                 forMode:NSRunLoopCommonModes];
}
//断开连接
- (void)disConnected{

    [self.socket disconnect];
}
//断开之后重新连接
- (void)socketDidDisconnect:(GCDAsyncSocket *)sock withError:(NSError *)err
{
    //这里可以列举枚举值
    //因用户自动断开 不自动连接
    if (self.offlineError == SZYSocketOfflineByServer) {
        [self.longConnectTimer invalidate];
        self.longConnectTimer = nil;
        [self.socket setDelegate:nil];
        [self.socket disconnect];
    //因服务器原因断开 自动连接
    }else if (self.offlineError == SZYSocketOfflineByServer){
    
        [self.longConnectTimer invalidate];
        self.longConnectTimer = nil;
        [self.socket setDelegate:nil];
        [self.socket disconnect];
        [self.socket setDelegate:self];
        [self.socket connectToHost:self.socketHost
                            onPort:self.socketPort
                             error:nil];
    //因Wifi原因断开 不自动连接
    }else{
        [self.longConnectTimer invalidate];
        self.longConnectTimer = nil;
        [self.socket setDelegate:nil];
        [self.socket disconnect];
    }
    
}
//写入数据
- (void)writeData:(NSData *)data withTimeout:(NSTimeInterval)timeout tag:(long)tag{

    [self.socket writeData:data withTimeout:-1 tag:100];
}
- (void)socket:(GCDAsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag {
    NSString *dataString = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
    NSLog(@"读取到的消息:%@", dataString);
}
//读取数据
- (void)readDataToData:(NSData *)data withTimeout:(NSTimeInterval)timeout tag:(long)tag{
    [self.socket readDataToData:data withTimeout:-1 tag:100];
    
}
- (void)socket:(GCDAsyncSocket *)sock didWriteDataWithTag:(long)tag {
    NSLog(@"didWriteDataWithTag");
}

有错误欢迎留言指正