通过keychain进行保存UUID

- (NSString *)getUUID{

NSError * error;
NSString *strUUID=[SSKeychain
passwordForService:keychain_service
account:keychain_account];

if (strUUID==nil||[strUUID
isEqualToString:@"" ]||strUUID.length==0)
{
strUUID=[self
get_uuid] ;
BOOL succcess= [SSKeychain
setPassword:strUUID forService:keychain_service
account:keychain_account
error:&error];
if(succcess)
{
NSLog(@"keychain success ");
}
}
return strUUID;

}

- (NSString*)get_uuid{

CFUUIDRef uuid_ref=CFUUIDCreate(nil);
CFStringRef uuid_string_ref=CFUUIDCreateString(nil, uuid_ref);
CFRelease(uuid_ref);
NSString *uuid=[NSString
stringWithString:(__bridge
NSString *)(uuid_string_ref)];
CFRelease(uuid_string_ref);
return uuid;

}通过keychain进行保存UUID，并且再删除应用后UUID不变
demo下载地址：https://github.com/Winter0801/demo.git