1.通过调用CFFUUIDCreate函数来生成机器唯一标识符，但每次调用以下函数返回的字符串都不一样，所以第一次调用后需把该字符串存储起来。这是官方API的建议方法
- (NSString *) uniqueString
{
CFUUIDRef unique = CFUUIDCreate(kCFAllocatorDefault);
NSString *result = [(NSString *)CFUUIDCreateString(kCFAllocatorDefault, unique) autorelease];
CFRelease(unique);
return result;
}
2.由于机器的mac地址都不一样，所以可通过获取mac地址后再进行md5加密处理后返回的字符串作为唯一标识码
- (NSString *) macaddress{
int mib[6];
size_t len;
char *buf;
unsigned char *ptr;
struct if_msghdr *ifm;
struct sockaddr_dl *sdl;
mib[0] = CTL_NET;
mib[1] = AF_ROUTE;
mib[2] = 0;
mib[3] = AF_LINK;
mib[4] = NET_RT_IFLIST;
if ((mib[5] = if_nametoindex("en0")) == 0) {
printf("Error: if_nametoindex error\n");
return NULL;
}
if (sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {
printf("Error: sysctl, take 1\n");
return NULL;
}
if ((buf = malloc(len)) == NULL) {
printf("Could not allocate memory. error!\n");
return NULL;
}
if (sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
printf("Error: sysctl, take 2");
return NULL;
}
ifm = (struct if_msghdr *)buf;
sdl = (struct sockaddr_dl *)(ifm + 1);
ptr = (unsigned char *)LLADDR(sdl);
NSString *outstring = [NSString stringWithFormat:@"%02X:%02X:%02X:%02X:%02X:%02X",
*ptr, *(ptr+1), *(ptr+2), *(ptr+3), *(ptr+4), *(ptr+5)];
free(buf);
return outstring;
}
- (NSString *) uniqueGlobalDeviceIdentifier{
NSString *macaddress = [[UIDevice currentDevice] macaddress];
NSString *uniqueIdentifier = [macaddress stringFromMD5];
return uniqueIdentifier;
}
NSString类别
@implementation NSString(MD5Addition)
- (NSString *) stringFromMD5{
if(self == nil || [self length] == 0)
return nil;
const char *value = [self UTF8String];
unsigned char outputBuffer[CC_MD5_DIGEST_LENGTH];
CC_MD5(value, strlen(value), outputBuffer);
NSMutableString *outputString = [[NSMutableString alloc] initWithCapacity:CC_MD5_DIGEST_LENGTH * 2];
for(NSInteger count = 0; count < CC_MD5_DIGEST_LENGTH; count++){
[outputString appendFormat:@"%02x",outputBuffer[count]];
}
return [outputString autorelease];
转http://blog.163.com/ray_jun/blog/static/1670536422011102744836300/
}