Question

我正在iPhone中开发应用程序，它是从网站动态获取数据，我正在检查Wifi和GPRS是否已连接但是当无法访问wifi时，应用程序崩溃。

我正在使用此方法检查连接。

+ (BOOL) isConnected {  
    // Part 1 - Create Internet socket addr of zero
    struct sockaddr_in zeroAddr;
    bzero(&zeroAddr, sizeof(zeroAddr));
    zeroAddr.sin_len = sizeof(zeroAddr);
    zeroAddr.sin_family = AF_INET;

    // Part 2- Create target in format need by SCNetwork
    SCNetworkReachabilityRef target = 
    SCNetworkReachabilityCreateWithAddress(NULL, (struct sockaddr *) &zeroAddr);

    // Part 3 - Get the flags
    SCNetworkReachabilityFlags flags;
    SCNetworkReachabilityGetFlags(target, &flags);

    // Part 4 - Create output
    NSString *sNetworkReachable;
    if (flags & kSCNetworkFlagsReachable)
        sNetworkReachable = @"YES";
    else
        sNetworkReachable = @"NO";

    NSString *sCellNetwork;
    if (flags & kSCNetworkReachabilityFlagsIsWWAN)
        sCellNetwork = @"YES";
    else
        sCellNetwork = @"NO";


    // Get host entry info for given host
    struct hostent *remoteHostEnt = gethostbyname("google.com");
    if(remoteHostEnt == nil ) return NO;

    // Get address info from host entry
    struct in_addr *remoteInAddr = (struct in_addr *) remoteHostEnt->h_addr_list[0];

    // Convert numeric addr to ASCII string
    char *sRemoteInAddr = inet_ntoa(*remoteInAddr);

    NSString *s = [[NSString alloc]
                 initWithFormat:
                 @"Network Reachable: %@\n"
                 @"Cell Network: %@\n"
                 @"Remote IP: %s\n",
                 sNetworkReachable,
                 sCellNetwork,
                 sRemoteInAddr];


    // Add text
    [sCellNetwork release];
    [sNetworkReachable release];

    NSLog(@"Message:%@",s);

    return [sNetworkReachable isEqualToString:@"YES"];  
}

由于瓦代夫卢

Answer 1

为什么要乱用IP地址？您可以直接致电SCNetworkReachabilityCreateWithName()：

SCNetworkReachabilityCreateWithName(kCFAllocatorDefault, "google.com");

Answer 2

在developer.apple.com

上搜索可达性示例应用程序

GitHub上还有一个开源NPReachability类，它执行相同的操作，但使用块作为处理程序。

Answer 3

您可以使用隐藏的UIWebView并加载网站。然后使用UIWebView.h中的方法检测加载是否成功。

检查网络连接iPhone

3 个答案: