讲解iOS应用之使用AsyncSocket库处理Socket通信的方法

//
//  LGSocketServe.h
//  AsyncSocketDemo
//

 

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

@interface LGSocketServe : NSObject<AsyncSocketDelegate>

+ (LGSocketServe *)sharedSocketServe;

@end

//
//  LGSocketServe.m
//  AsyncSocketDemo
//

 

#import "LGSocketServe.h"

@implementation LGSocketServe

static LGSocketServe *socketServe = nil;

#pragma mark public static methods

+ (LGSocketServe *)sharedSocketServe {
    @synchronized(self) {
        if(socketServe == nil) {
            socketServe = [[[self class] alloc] init];
        }
    }
    return socketServe;
}

+(id)allocWithZone:(NSZone *)zone
{
    @synchronized(self)
    {
        if (socketServe == nil)
        {
            socketServe = [super allocWithZone:zone];
            return socketServe;
        }
    }
    return nil;
}  

@end

@property (nonatomic, strong) AsyncSocket         *socket;       // socket

 

//  socket连接
- (void)startConnectSocket;
LGSocketServe.m

//自己设定
#define HOST @"192.168.0.1"
#define PORT 8080

//设置连接超时
#define TIME_OUT 20

- (void)startConnectSocket
{
    self.socket = [[AsyncSocket alloc] initWithDelegate:self];
    [self.socket setRunLoopModes:[NSArray arrayWithObject:NSRunLoopCommonModes]];
    if ( ![self SocketOpen:HOST port:PORT] )
    {

    }

}

- (NSInteger)SocketOpen:(NSString*)addr port:(NSInteger)port
{

    if (![self.socket isConnected])
    {
        NSError *error = nil;
        [self.socket connectToHost:addr onPort:port withTimeout:TIME_OUT error:&error];
    }

    return 0;
}

- (void)onSocket:(AsyncSocket *)sock didConnectToHost:(NSString *)host port:(UInt16)port
{
    //这是异步返回的连接成功，
    NSLog(@"didConnectToHost");
}

@property (nonatomic, retain) NSTimer             *heartTimer;   // 心跳计时器
LGSocketServe.m

 

- (void)onSocket:(AsyncSocket *)sock didConnectToHost:(NSString *)host port:(UInt16)port
{
    //这是异步返回的连接成功，
    NSLog(@"didConnectToHost");

    //通过定时器不断发送消息，来检测长连接
    self.heartTimer = [NSTimer scheduledTimerWithTimeInterval:2 target:self selector:@selector(checkLongConnectByServe) userInfo:nil repeats:YES];
    [self.heartTimer fire];
}

// 心跳连接
-(void)checkLongConnectByServe{

    // 向服务器发送固定可是的消息，来检测长连接
    NSString *longConnect = @"connect is here";
    NSData   *data  = [longConnect dataUsingEncoding:NSUTF8StringEncoding];
    [self.socket writeData:data withTimeout:1 tag:1];
}

// 断开socket连接
-(void)cutOffSocket;
LGSocketServe.m

 

-(void)cutOffSocket
{
    self.socket.userData = SocketOfflineByUser;
    [self.socket disconnect];
}

- (void)onSocket:(AsyncSocket *)sock willDisconnectWithError:(NSError *)err
{

 

    NSLog(@" willDisconnectWithError %ld   err = %@",sock.userData,[err description]);
    if (err.code == 57) {
        self.socket.userData = SocketOfflineByWifiCut;
    }

}

- (void)onSocketDidDisconnect:(AsyncSocket *)sock
{

 

    NSLog(@"7878 sorry the connect is failure %ld",sock.userData);

    if (sock.userData == SocketOfflineByServer) {
        // 服务器掉线，重连
        [self startConnectSocket];
    }
    else if (sock.userData == SocketOfflineByUser) {

        // 如果由用户断开，不进行重连
        return;
    }else if (sock.userData == SocketOfflineByWifiCut) {

        // wifi断开，不进行重连
        return;
    }

}

// 发送消息
- (void)sendMessage:(id)message;
LGSocketServe.m

 

//设置写入超时 -1 表示不会使用超时
#define WRITE_TIME_OUT -1

- (void)sendMessage:(id)message
{
    //像服务器发送数据
    NSData *cmdData = [message dataUsingEncoding:NSUTF8StringEncoding];
    [self.socket writeData:cmdData withTimeout:WRITE_TIME_OUT tag:1];
}

//发送消息成功之后回调
- (void)onSocket:(AsyncSocket *)sock didWriteDataWithTag:(long)tag
{

}

//设置读取超时 -1 表示不会使用超时
#define READ_TIME_OUT -1

 

#define MAX_BUFFER 1024

//发送消息成功之后回调
- (void)onSocket:(AsyncSocket *)sock didWriteDataWithTag:(long)tag
{
    //读取消息
    [self.socket readDataWithTimeout:-1 buffer:nil bufferOffset:0 maxLength:MAX_BUFFER tag:0];
}

//接受消息成功之后回调
- (void)onSocket:(AsyncSocket *)sock didReadData:(NSData *)data withTag:(long)tag
{
    //服务端返回消息数据量比较大时，可能分多次返回。所以在读取消息的时候，设置MAX_BUFFER表示每次最多读取多少，当data.length < MAX_BUFFER我们认为有可能是接受完一个完整的消息，然后才解析
    if( data.length < MAX_BUFFER )
    {
        //收到结果解析...
        NSDictionary *dic = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingMutableLeaves error:nil];
        NSLog(@"%@",dic);
        //解析出来的消息，可以通过通知、代理、block等传出去

    }

    [self.socket readDataWithTimeout:READ_TIME_OUT buffer:nil bufferOffset:0 maxLength:MAX_BUFFER tag:0];

- (void)onSocket:(AsyncSocket *)sock willDisconnectWithError:(NSError *)err
{
    NSData * unreadData = [sock unreadData]; // ** This gets the current buffer
    if(unreadData.length > 0) {
        [self onSocket:sock didReadData:unreadData withTag:0]; // ** Return as much data that could be collected
    } else {

 

        NSLog(@" willDisconnectWithError %ld   err = %@",sock.userData,[err description]);
        if (err.code == 57) {
            self.socket.userData = SocketOfflineByWifiCut;
        }
    }

}

 LGSocketServe *socketServe = [LGSocketServe sharedSocketServe];
//socket连接前先断开连接以免之前socket连接没有断开导致闪退
[socketServe cutOffSocket];
socketServe.socket.userData = SocketOfflineByServer;
[socketServe startConnectSocket];

 

//发送消息 @"hello world"只是举个列子，具体根据服务端的消息格式
[socketServe sendMessage:@"hello world"];