在之前的版本是可以使用UDID获取iOS设备唯一标识，
NSString *udidString = [[UIDevice currentDevice] uniqueIdentifier];
但是iOS5及以后，被苹果禁止使用了（弃用了）
而直接获取的UUID系统不会存储，每次调用的时候都会获得一个新的UUID标示符
一般获取UUID的方法如下
我们可以通过持久存储这个标识符，来保证即使重新加载，删除后重装应用都能够唯一标识，以下的方式通过获取到UUID后存入系统中的keychain中，来保证以后每次可以得到相同的唯一标志。
代码如下：
#import "UUIDTool.h"
NSString * const kUUIDKey = @"com.myApp.uuid";
@implementation UUIDTool
#pragma mark - 获取到UUID后存入系统中的keychain中
+ (NSString *)getUUIDInKeychain {
// 1.直接从keychain中获取UUID
NSString *getUDIDInKeychain = (NSString *)[UUIDTool load:kUUIDKey];
NSLog(@"从keychain中获取UUID%@", getUDIDInKeychain);
// 2.如果获取不到，需要生成UUID并存入系统中的keychain
if (!getUDIDInKeychain || [getUDIDInKeychain isEqualToString:@""] || [getUDIDInKeychain isKindOfClass:[NSNull class]]) {
// 2.1 生成UUID
CFUUIDRef puuid = CFUUIDCreate(nil);
CFStringRef uuidString = CFUUIDCreateString(nil, puuid);
NSString *result = (NSString *)CFBridgingRelease(CFStringCreateCopy(NULL, uuidString));
CFRelease(puuid);
CFRelease(uuidString);
NSLog(@"生成UUID：%@",result);
// 2.2 将生成的UUID保存到keychain中
[UUIDTool save:kUUIDKey data:result];
// 2.3 从keychain中获取UUID
getUDIDInKeychain = (NSString *)[UUIDTool load:kUUIDKey];
}
return getUDIDInKeychain;
}
#pragma mark - 删除存储在keychain中的UUID
+ (void)deleteKeyChain {
[self delete:kUUIDKey];
}
#pragma mark - 私有方法
+ (NSMutableDictionary *)getKeyChainQuery:(NSString *)service {
return [NSMutableDictionary dictionaryWithObjectsAndKeys:(id)kSecClassGenericPassword,(id)kSecClass,service,(id)kSecAttrService,service,(id)kSecAttrAccount,(id)kSecAttrAccessibleAfterFirstUnlock,(id)kSecAttrAccessible, nil];
}
// 从keychain中获取UUID
+ (id)load:(NSString *)service {
id ret = nil;
NSMutableDictionary *keychainQuery = [self getKeyChainQuery:service];
[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 *exception) {
NSLog(@"Unarchive of %@ failed: %@", service, exception);
}
@finally {
NSLog(@"finally");
}
}
if (keyData) {
CFRelease(keyData);
}
NSLog(@"ret = %@", ret);
return ret;
}
+ (void)delete:(NSString *)service {
NSMutableDictionary *keychainQuery = [self getKeyChainQuery:service];
SecItemDelete((CFDictionaryRef)keychainQuery);
}
// 将生成的UUID保存到keychain中
+ (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 search dictionary(Attention:the data format)
[keychainQuery setObject:[NSKeyedArchiver archivedDataWithRootObject:data] forKey:(id)kSecValueData];
// Add item to keychain with the search dictionary
SecItemAdd((CFDictionaryRef)keychainQuery, NULL);
}
另外附上GitHub上的Demo链接：https://github.com/rambocai/ZYUUID-Emon.git
作者：雪落倾城
链接：https://www.jianshu.com/p/0dce89cdf9f6
來源：简书
简书著作权归作者所有，任何形式的转载都请联系作者获得授权并注明出处。