來自:http://zachwaugh.me/posts/programmatically-retrieving-ip-address-of-iphone/
對於我的應用程序,QuickPic,我需要向用戶展示自己的iPhone的IP地址,這樣他們就可以鍵入網址到瀏覽器。在iPhoneSDK沒有提供簡單的方法來獲取WiFi連接的IP地址。也有一些無證工作方法([NSHost地址]),但我不想冒險他們拉了出來,使我的應用程序崩潰。所以我寫了一些C代碼(從各種來源拼湊起來的),將依次通過網絡接口和獲取IP地址。
這裏有一個Objective-C的方法來檢索WiFi連接作爲的NSString的IP地址。
- (NSString *)getIPAddress
{
NSString *address = @"error";
struct ifaddrs *interfaces = NULL;
struct ifaddrs *temp_addr = NULL;
int success = 0;
// retrieve the current interfaces - returns 0 on success
success = getifaddrs(&interfaces);
if (success == 0) {
// 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;
}
如果它沒有起作用或者報錯了,你可能需要包括在你的類實現頂部下面的C頭文件。
#include <ifaddrs.h>
#include <arpa/inet.h>
我自己試用:
當引入<ifaddrs.h>時,我的代碼報錯了,把它改爲#import<ifaddrs.h>就好了。
後來發現這只是能夠獲取Wi-Fi下的IP,之後在Stack Overflow上看到一個加強的版本;
在http://stackoverflow.com/questions/7072989/iphone-ipad-how-to-get-my-ip-address-programmatically有更爲簡單的獲取IP地址的方法,並且能實時更新。
以下爲詳細方法:
#include <ifaddrs.h>
#include <arpa/inet.h>
#include <net/if.h>
#define IOS_CELLULAR @"pdp_ip0"
#define IOS_WIFI @"en0"
#define IOS_VPN @"utun0"
#define IP_ADDR_IPv4 @"ipv4"
#define IP_ADDR_IPv6 @"ipv6"
- (NSString *)getIPAddress:(BOOL)preferIPv4
{
NSArray *searchArray = preferIPv4 ?
@[ IOS_VPN @"/" IP_ADDR_IPv4, IOS_VPN @"/" IP_ADDR_IPv6, IOS_WIFI @"/" IP_ADDR_IPv4, IOS_WIFI @"/" IP_ADDR_IPv6, IOS_CELLULAR @"/" IP_ADDR_IPv4, IOS_CELLULAR @"/" IP_ADDR_IPv6 ] :
@[ IOS_VPN @"/" IP_ADDR_IPv6, IOS_VPN @"/" IP_ADDR_IPv4, IOS_WIFI @"/" IP_ADDR_IPv6, IOS_WIFI @"/" IP_ADDR_IPv4, IOS_CELLULAR @"/" IP_ADDR_IPv6, IOS_CELLULAR @"/" IP_ADDR_IPv4 ] ;
NSDictionary *addresses = [self getIPAddresses];
NSLog(@"addresses: %@", addresses);
__block NSString *address;
[searchArray enumerateObjectsUsingBlock:^(NSString *key, NSUInteger idx, BOOL *stop)
{
address = addresses[key];
if(address) *stop = YES;
} ];
return address ? address : @"0.0.0.0";
}
- (NSDictionary *)getIPAddresses
{
NSMutableDictionary *addresses = [NSMutableDictionary dictionaryWithCapacity:8];
// retrieve the current interfaces - returns 0 on success
struct ifaddrs *interfaces;
if(!getifaddrs(&interfaces)) {
// Loop through linked list of interfaces
struct ifaddrs *interface;
for(interface=interfaces; interface; interface=interface->ifa_next) {
if(!(interface->ifa_flags & IFF_UP) /* || (interface->ifa_flags & IFF_LOOPBACK) */ ) {
continue; // deeply nested code harder to read
}
const struct sockaddr_in *addr = (const struct sockaddr_in*)interface->ifa_addr;
char addrBuf[ MAX(INET_ADDRSTRLEN, INET6_ADDRSTRLEN) ];
if(addr && (addr->sin_family==AF_INET || addr->sin_family==AF_INET6)) {
NSString *name = [NSString stringWithUTF8String:interface->ifa_name];
NSString *type;
if(addr->sin_family == AF_INET) {
if(inet_ntop(AF_INET, &addr->sin_addr, addrBuf, INET_ADDRSTRLEN)) {
type = IP_ADDR_IPv4;
}
} else {
const struct sockaddr_in6 *addr6 = (const struct sockaddr_in6*)interface->ifa_addr;
if(inet_ntop(AF_INET6, &addr6->sin6_addr, addrBuf, INET6_ADDRSTRLEN)) {
type = IP_ADDR_IPv6;
}
}
if(type) {
NSString *key = [NSString stringWithFormat:@"%@/%@", name, type];
addresses[key] = [NSString stringWithUTF8String:addrBuf];
}
}
}
// Free memory
freeifaddrs(interfaces);
}
return [addresses count] ? addresses : nil;
}