iOS编程——通过UUID和KeyChain来代替Mac地址实现iOS设备的唯一标示(OC版)
很多的应用都需要用到手机的唯一标示,而且要求这个唯一标示不能因为应用app的卸载或者改变而变化。
在iOS7以前是可以通过Mac地址来实现这个功能的,但是iOS7(包含)以后是无法获得Mac地址的;苹果官方推荐使用UUID,但是每次随着APP的卸载重装,UUID会随之发生变化,那该如何处理呢?
我们需要一个能在app卸载重装后不会改变的值,而keyChain恰巧就可以做到。配合UUID就可以实现了!让我们来分析下:
1.我们首先需要导入Security.frameWork(keychain依赖它),然后需要一个keychain管理器,一个uuid管理器,文件组成如下:
2.首先来看MyKeychainManager,其实就是对keychain的增、删、改、查,类似于数据库的处理。
先通过.h文件来开放下增、删、改、查四个接口:
#import <Foundation/Foundation.h> @interface MyKeyChainManager : NSObject + (NSMutableDictionary *)getKeychainQuery:(NSString *)service; + (void)save:(NSString *)service data:(id)data; + (id)load:(NSString *)service; + (void)delete:(NSString *)service; @end
.m文件实现接口,keychain的使用网上很多,直接贴代码了:
#import "MyKeyChainManager.h"
@implementation MyKeyChainManager : NSObject
+ (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) {
NSLog(@"Unarchive of %@ failed: %@", service, e);
} @finally {
}
}
return ret;
}
+ (void)delete:(NSString *)service {
NSMutableDictionary *keychainQuery = [self getKeychainQuery:service];
SecItemDelete((__bridge_retained CFDictionaryRef)keychainQuery);
}
@end