iOS 获取用户唯一标识

方式使用 keyChain + uuid
1.需要在xcode -> project ->target ->capabilities 中添加 keychain sharing
2.在项目中添加下面两个文件

#import 

NS_ASSUME_NONNULL_BEGIN

@interface DeviceId : NSObject
+ (NSString *)getUUIDByKeyChain;
+ (void)save:(NSString*)service data:(id)data;
+ (id)load:(NSString*)service;
+ (void)deleteKeyData:(NSString*)service;
@end

NS_ASSUME_NONNULL_END

#import "DeviceId.h"
#import 
@implementation DeviceId


/**  获取UUID*/
+ (NSString *)getUUIDByKeyChain{
    NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];//获取app版本信息
    NSString *key = [NSString stringWithFormat:@"%@.uniqueid",[infoDictionary objectForKey:@"CFBundleIdentifier"]];
    NSString*strUUID = (NSString*)[DeviceId load:key];
    if([strUUID isEqualToString:@""]|| !strUUID)
    {
        strUUID = [UIDevice currentDevice].identifierForVendor.UUIDString;
        
        if(strUUID.length ==0 || [strUUID isEqualToString:@"00000000-0000-0000-0000-000000000000"])
        {
            CFUUIDRef uuidRef= CFUUIDCreate(kCFAllocatorDefault);
            strUUID = (NSString*)CFBridgingRelease(CFUUIDCreateString(kCFAllocatorDefault,uuidRef));
            CFRelease(uuidRef);
        }
        //将该uuid保存到keychain
        [DeviceId save:key data:strUUID];
    }
    return strUUID;
}


+ (NSMutableDictionary*)getKeychainQuery:(NSString*)service {
    return[NSMutableDictionary dictionaryWithObjectsAndKeys:
           (id)kSecClassGenericPassword,(id)kSecClass,
           service,(id)kSecAttrService,
           service,(id)kSecAttrAccount,
           (id)kSecAttrAccessibleAfterFirstUnlock,(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((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

3.在代码中调用

    NSString *uuid = [DeviceId getUUIDByKeyChain];
    NSLog(@"uuid = %@",uuid);