NSHost 花费了很长的时间

Question

我有一个 iPhone 应用程序，它是现有服务器应用程序的客户端。

我正在使用以下代码进行连接，并且该代码工作正常。 今天我开始从事这个项目，但发生了一些奇怪的事情。

当我单击“连接”时，NSHost 需要大约 30-45 秒来解析并连接到主机。 连接建立后，数据传输速度正常且快速。

我有原始客户端软件（PC应用程序）连接到同一服务器，并且连接立即处理！

也许有人可以阐明这个主题...

-(IBAction)tryConnection{
    [self showLogoffButtons];
    iPhone_PNPAppDelegate *mainDelegate = (iPhone_PNPAppDelegate *)[[UIApplication sharedApplication] delegate];
    settings=mainDelegate.settings; 
    [activityindicator startAnimating];
    sendState=0;

    NSHost* host;

    //30-45 second pause happens here (since I am using an IP Address)
    host = [NSHost hostWithAddress:settings.masterLocation];
    //NSHost returns (eventually) with the correct connection.

    if (!host)  {
        host = [NSHost hostWithName:settings.masterLocation];
    }
    if( host ) {
        [NSStream getStreamsToHost:host port:[settings.masterPort intValue] inputStream:&iStream outputStream:&oStream] ;
        if( nil != iStream && nil != oStream ) {
            [iStream retain];
            [oStream retain];
            [iStream setDelegate:self];
            [oStream setDelegate:self];
            [iStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
            [oStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
            [iStream open];
            [oStream open]; 
        }else{
            [self resetConnectionAndScreen];
            self.navigationItem.prompt=@"Connection Error! Please check connection settings.";
        }

    }else{
        [self resetConnectionAndScreen];
        self.navigationItem.prompt=@"Connection Error! Please check connection settings.";
    }
}

//我现在也收到这些警告。**.. wth？！ :)

• 警告：没有找到 '+hostWithAddress:' 方法
• 警告：（没有匹配方法签名的消息
• 警告：没有找到 '+hostWithName:' 方法
• 警告：'NSStream' 可能不会响应 '+getStreamsToHost:port:inputStream:outputStream: '

Answer 1

我已将代码更新为以下内容，这解决了我的问题。

-(IBAction)tryConnection{   
    CFReadStreamRef readStream = NULL;
    CFWriteStreamRef writeStream = NULL;
    CFStreamCreatePairWithSocketToHost(kCFAllocatorDefault, (CFStringRef)settings.masterLocation, [settings.masterPort intValue], &readStream, &writeStream);
    if (readStream && writeStream) {
        CFReadStreamSetProperty(readStream, kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);
        CFWriteStreamSetProperty(writeStream, kCFStreamPropertyShouldCloseNativeSocket, kCFBooleanTrue);

        iStream = (NSInputStream *)readStream;
        [iStream retain];
        [iStream setDelegate:self];
        [iStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
        [iStream open];

        oStream = (NSOutputStream *)writeStream;
        [oStream retain];
        [oStream setDelegate:self];
        [oStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
        [oStream open];     
    }
    if (readStream) CFRelease(readStream);
    if (writeStream) CFRelease(writeStream);
}

Answer 2

这是使用 cfsockets

http://randomsnippetsofusefulstuff.blogspot.com/进行联网的另一种方式