oc唯一标时一部设备

MyUUIDManager.h

#import <Foundation/Foundation.h>

NS_ASSUME_NONNULL_BEGIN

@interface MyUUIDManager : NSObject
+(void)saveUUID:(NSString *)uuid;

+(NSString *)getUUID;

+(void)deleteUUID;
@end

NS_ASSUME_NONNULL_END

MyUUIDManager.m

#import "MyUUIDManager.h"
#import "MyKeyChainManager.h"
@implementation MyUUIDManager
static NSString * const KEY_IN_KEYCHAIN = @"com.myuuid.uuid";

+(void)saveUUID:(NSString *)uuid{
    if (uuid && uuid.length > 0) {
        [MyKeyChainManager save:KEY_IN_KEYCHAIN data:uuid];
    }
}

+(NSString *)getUUID{
    //先获取keychain里面的UUID字段，看是否存在
    NSString *uuid = (NSString *)[MyKeyChainManager load:KEY_IN_KEYCHAIN];

    //如果不存在则为首次获取UUID，所以获取保存。
    if (!uuid || uuid.length == 0) {
        CFUUIDRef puuid = CFUUIDCreate( nil );

        CFStringRef uuidString = CFUUIDCreateString( nil, puuid );

        uuid = [NSString stringWithFormat:@"%@", uuidString];

        [self saveUUID:uuid];

        CFRelease(puuid);

        CFRelease(uuidString);
    }

    return uuid;
}

+(void)deleteUUID{
    [MyKeyChainManager delete:KEY_IN_KEYCHAIN];
}

@end

MyKeyChainManager.h

#import <Foundation/Foundation.h>

NS_ASSUME_NONNULL_BEGIN

@interface MyKeyChainManager : NSObject

+ (void)save:(NSString *)service data:(id)data;
+ (id)load:(NSString *)service ;
+ (void)delete:(NSString *)service ;
@end

NS_ASSUME_NONNULL_END

MyKeyChainManager.m

#import "MyKeyChainManager.h"

@implementation MyKeyChainManager

+ (NSMutableDictionary *)getKeychainQuery:(NSString *)service {
    return [NSMutableDictionary dictionaryWithObjectsAndKeys:
            (__bridge_transfer id)kSecClassGenericPassword,(__bridge_transfer id)kSecClass,
            service, (__bridge_transfer id)kSecAttrService,
            service, (__bridge_transfer id)kSecAttrAccount,
            (__bridge_transfer id)kSecAttrAccessibleAfterFirstUnlock,(__bridge_transfer id)kSecAttrAccessible,
            nil];
}

+ (void)save:(NSString *)service data:(id)data {
    //Get search dictionary
    NSMutableDictionary *keychainQuery = [self getKeychainQuery:service];
    //Delete old item before add new item
    SecItemDelete((__bridge_retained CFDictionaryRef)keychainQuery);
    //Add new object to search dictionary(Attention:the data format)
    [keychainQuery setObject:[NSKeyedArchiver archivedDataWithRootObject:data] forKey:(__bridge_transfer id)kSecValueData];
    //Add item to keychain with the search dictionary
    SecItemAdd((__bridge_retained CFDictionaryRef)keychainQuery, NULL);
}

+ (id)load:(NSString *)service {
    id ret = nil;
    NSMutableDictionary *keychainQuery = [self getKeychainQuery:service];
    //Configure the search setting
    [keychainQuery setObject:(id)kCFBooleanTrue forKey:(__bridge_transfer id)kSecReturnData];
    [keychainQuery setObject:(__bridge_transfer id)kSecMatchLimitOne forKey:(__bridge_transfer id)kSecMatchLimit];
    CFDataRef keyData = NULL;
    if (SecItemCopyMatching((__bridge_retained CFDictionaryRef)keychainQuery, (CFTypeRef *)&keyData) == noErr) {
        @try {
            ret = [NSKeyedUnarchiver unarchiveObjectWithData:(__bridge_transfer NSData *)keyData];
        } @catch (NSException *e) {

        } @finally {
        }
    }
    return ret;
}

+ (void)delete:(NSString *)service {
    NSMutableDictionary *keychainQuery = [self getKeychainQuery:service];
    SecItemDelete((__bridge_retained CFDictionaryRef)keychainQuery);
}

@end

使用：NSLog(@"%@",[MyUUIDManager getUUID]);

//如果uuid为空

if(!uuid){
        // 获取UUID 这个是要引入<AdSupport/AdSupport.h>的
        if ( [[ASIdentifierManager sharedManager] isAdvertisingTrackingEnabled] ) {
            uuid = [[[ASIdentifierManager sharedManager] advertisingIdentifier] UUIDString];
            return uuid;
        }else{
            return @"";
        }
    }