-(void)sendBtnClick:(id)sender
{
    _asyncSocket = nil;
    for (int i = 0; i<3; i++) {
        NSLog(@"第%d次",i);
        [self send];
    }
}
-(void)send
{
    if (!_asyncSocket)
    {
        _asyncSocket = [[AsyncSocket alloc]initWithDelegate:self];
        NSString *host = @"172.17.73.123";
        int nPort = 8484;
        NSError *error = nil;
        //[_asyncSocket connectToHost:host onPort:nPort error:&error];
        if ([_asyncSocket connectToHost:host onPort:nPort withTimeout:5 error:&error]) {
            NSData *imageData = UIImageJPEGRepresentation([UIImage imageNamed:@"1.jpg"], 1);
            [_asyncSocket writeData:imageData withTimeout:-1 tag:1];
        }else{
            NSLog(@"无法连接，原因是:%@",error);
        }
    }
    sleep(5);
}

#pragma delegate
- (void)onSocket:(AsyncSocket *)sock willDisconnectWithError:(NSError *)err
{
    NSLog(@"Info___willDisconnectWithError\n");
    NSLog(@"%@",err);
    [sock disconnectAfterWriting];
}

- (void)onSocket:(AsyncSocket *)sock didConnectToHost:(NSString *)host port:(UInt16)port
{
    NSLog(@"Info___didConnectToHost\n");
    NSLog(@"Socket did Connect to host: %@:%u", host, port);
    _asyncSocket = nil;
    [sock disconnectAfterWriting];
}