開發(fā)中經(jīng)常需要獲取設(shè)備的唯一標(biāo)識符蹦疑，app的更新迭代肌蜻，刪除，系統(tǒng)升級等必尼，都不會影響keychain數(shù)據(jù)中的保存（系統(tǒng)恢復(fù)出廠設(shè)置等，恢復(fù)型操作除外）篡撵，所以Keychain顯得尤為重要判莉，
1.將Keychain Sharing按鈕打開
2.
#import <Foundation/Foundation.h>
@interface UUID : NSObject
+(NSString*)getUUID;
@end
#import "UUID.h"
#import "KeyChainStore.h"
@implementation UUID
+(NSString*)getUUID {
? ? NSString *strUUID =(NSString*)[KeyChainStore load:@"com.company.app.usernamepassword"];
? ? //首次執(zhí)行該方法時，uuid為空
? ? if([strUUID isEqualToString:@""]|| !strUUID){
?? ? ? ? ? ? //生成一個uuid的方法
? ? ? ? ? ? CFUUIDRef uuidRef= CFUUIDCreate(kCFAllocatorDefault);
?? ? ? ? ? ? strUUID =(NSString*)CFBridgingRelease(CFUUIDCreateString(kCFAllocatorDefault,uuidRef));
? ? ? ? ? ? //將該uuid保存到keychain
? ? ? ? ? ? [KeyChainStore save:@"com.company.app.usernamepassword" data:strUUID];
? ? ? ? }
? ? ? ? return strUUID;
}
@end
3.
#import <Foundation/Foundation.h>
@interface KeyChainStore : NSObject
+(void)save:(NSString*)service data:(id)data;
+(id)load:(NSString*)service;
+(void)deleteKeyData:(NSString*)service;
@end
#import "KeyChainStore.h"
@implementation KeyChainStore
+(NSMutableDictionary*)getKeychainQuery:(NSString*)service {
? ? return[NSMutableDictionary dictionaryWithObjectsAndKeys:
? ? ? ? ? ? (id)kSecClassGenericPassword,(id)kSecClass,
? ? ? ? ? ? service,(id)kSecAttrService,
? ? ? ? ? ? service,(id)kSecAttrAccount,
? ? ? ? ? ? nil];
}
+(void)save:(NSString*)service data:(id)data {
? ? //Get search dictionary
? ? NSMutableDictionary*keychainQuery =[self getKeychainQuery:service];
? ? //Delete old item before add new item
? ? SecItemDelete((CFDictionaryRef)keychainQuery);
? ? //Add new object to searchdictionary(Attention:the data format)
? ? [keychainQuery setObject:[NSKeyedArchiver archivedDataWithRootObject:data]forKey:(id)kSecValueData];
? ? //Add item to keychain with the searchdictionary
? ? SecItemAdd((CFDictionaryRef)keychainQuery,NULL);
}
+(id)load:(NSString*)service {
? ? id ret =nil;
? ? NSMutableDictionary*keychainQuery =[self getKeychainQuery:service];
? ? //Configure the search setting
? ? //Since in our simple case we areexpecting only a single attribute to be returned(the password)wecan set the attribute kSecReturnData to kCFBooleanTrue
? ? [keychainQuery setObject:(id)kCFBooleanTrue forKey:(id)kSecReturnData];
? ? [keychainQuery setObject:(id)kSecMatchLimitOne forKey:(id)kSecMatchLimit];
? ? CFDataRef keyData =NULL;
? ? if(SecItemCopyMatching((CFDictionaryRef)keychainQuery,(CFTypeRef*)&keyData)==noErr){
? ? @try{
? ? ? ? ret =[NSKeyedUnarchiver unarchiveObjectWithData:(__bridge NSData*)keyData];
? ? ? ? }@catch(NSException *e){
? ? ? ? ? ? ? ? NSLog(@"Unarchiveof %@ failed: %@",service,e);
? ? ? ? }@finally{
? ? ? ? }
? ? }
? ? if(keyData)
? ? ? ? CFRelease(keyData);
? ? return ret;
}
+(void)deleteKeyData:(NSString*)service {
? ? NSMutableDictionary*keychainQuery =[self getKeychainQuery:service];
? ? SecItemDelete((CFDictionaryRef)keychainQuery);
}
@end
4.在需要獲取設(shè)備唯一標(biāo)識符的地方導(dǎo)入以下兩個頭文件育谬，再調(diào)用 [UUID getUUID]方法即可
#import "UUID.h"
#import "KeyChainStore.h"
params[@"imei"]=[UUID getUUID];
