Question

我编写了一个程序，使用Apple的流编程指南中概述的NSStream协议连接到给定IP上的服务器。数据的连接和传输完美无缺，但是如果用户指定了错误的IP并且程序试图打开流，则会导致程序无响应。

根据我的阅读，handleEvent方法检测到流错误，但是当我检查eventCode == NSStreamEventErrorOccurred的条件时，似乎什么都没发生。我的连接代码如下：

NSString *hostString = ipField.text;

    CFReadStreamRef readStream;

    CFWriteStreamRef writeStream;

    CFStreamCreatePairWithSocketToHost(NULL, (CFStringRef)hostString, 10001, &readStream, &writeStream);



    inputStream = (NSInputStream *)readStream;

    outputStream = (NSOutputStream *)writeStream;

    [inputStream setDelegate:self];

    [outputStream setDelegate:self];

    [inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];

    [outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];

    [inputStream open];

    [outputStream open];

如果无法建立连接，是否可以指定超时值或允许按钮触发关闭流？

Answer 1

任何关于我如何指定的想法超时值或允许按钮触发关闭流如果无法建立连接？

使用NSTimer。

在你的.h：

...
@interface MyViewController : UIViewController
{
    ...
    NSTimer* connectionTimeoutTimer;
    ...
}
...

在你的.m：

...
@interface MyViewController ()
@property (nonatomic, retain) NSTimer* connectionTimeoutTimer;
@end

@implementation MyViewController

...
@synthesize connectionTimeoutTimer;
...

- (void)dealloc
{
    [self stopConnectionTimeoutTimer];
    ...
}

// Call this when you initiate the connection
- (void)startConnectionTimeoutTimer
{
    [self stopConnectionTimeoutTimer]; // Or make sure any existing timer is stopped before this method is called

    NSTimeInterval interval = 3.0; // Measured in seconds, is a double

    self.connectionTimeoutTimer = [NSTimer scheduledTimerWithTimeInterval:interval
                                                                   target:self
                                                                 selector:@selector(handleConnectionTimeout:)
                                                                 userInfo:nil
                                                                  repeats:NO];
}

- (void)handleConnectionTimeout
{
    // ... disconnect ...
}

// Call this when you successfully connect
- (void)stopConnectionTimeoutTimer
{
    if (connectionTimeoutTimer)
    {
        [connectionTimeoutTimer invalidate];
        [connectionTimeoutTimer release];
        connectionTimeoutTimer = nil;
    }
}

iPhone：使用NSStream捕获连接错误

1 个答案: