获取本机IP地址

这里有两种方法：

 //获取本机IP
 - (NSString *)localIPAddress
 {
     NSString *localIP = nil;
     struct ifaddrs *addrs;
     if (getifaddrs(&addrs)==) {
         const struct ifaddrs *cursor = addrs;
         while (cursor != NULL) {
             if (cursor->ifa_addr->sa_family == AF_INET && (cursor->ifa_flags & IFF_LOOPBACK) == )
             {
                 {
                     localIP = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)cursor->ifa_addr)->sin_addr)];
                     break;
                 }
             }
             cursor = cursor->ifa_next;
         }
         freeifaddrs(addrs);
     }
     return localIP;
 }

 // 获取本机IP地址
 - (NSString *)getIPAddress
 {
     NSString *address = @"error";
     struct ifaddrs *interfaces = NULL;
     struct ifaddrs *temp_addr = NULL;
     int success = ;

     // retrieve the current interfaces - returns 0 on success
     success = getifaddrs(&interfaces);
     if (success == ) {
         // Loop through linked list of interfaces
         temp_addr = interfaces;
         while (temp_addr != NULL) {
             if( temp_addr->ifa_addr->sa_family == AF_INET) {
                 // Check if interface is en0 which is the wifi connection on the iPhone
                 if ([[NSString stringWithUTF8String:temp_addr->ifa_name] isEqualToString:@"en0"]) {
                     // Get NSString from C String
                     address = [NSString stringWithUTF8String:inet_ntoa(((struct sockaddr_in *)temp_addr->ifa_addr)->sin_addr)];
                 }
             }

             temp_addr = temp_addr->ifa_next;
         }
     }

     // Free memory
     freeifaddrs(interfaces);

     return address;
 }