iOS Keychain （钥匙串）简单封装

1 、Keychain 是一个非常好用的本地存储工具 完全可以替代NSuserDefault 来使用并且比NSuserDefault更安全  。

 2 、Keychain相对于 NSuserDefault最主要的一点就是 NSuserDefault 只能项目内访问  Keychain 说是所有项目公用的  可以做到跨项目读取数据。

3、Keychain经常用来保存用的的账户 密码信息  Keychain在内部实现上实际还是用的数据库 来存储的这里不多做解释

4、用法 这里写死了数据 具体可以根据实际情况 和NSuserDefault 用法一样

  [ZFYKeychain savePassWord:@"aaa1" forKey:@"aaa"];

    NSLog(@"%@", [ZFYKeychain readPassWordObjectForKey:@"aaa"]);

    

    [ZFYKeychain savePassWord:@"bbb1" forKey:@"bbb"];

    NSLog(@"%@", [ZFYKeychain readPassWordObjectForKey:@"bbb"]);

    

    

    [ZFYKeychain deletePassWordObjectForKey:@"aaa"];

     NSLog(@"%@", [ZFYKeychain readPassWordObjectForKey:@"aaa"]);

     NSLog(@"%@", [ZFYKeychain readPassWordObjectForKey:@"bbb"]);

5、设置跨APP 共享数据 

第一种方法：通过plist方式进行

1>创建一个新文件，选择Property list文件。

2>创建一个新的子节点，取名为keychain-access-groups

3>修改节点keychain-access-groups的类型为Array

4>在keychain-access-groups节点下添加子节点，填入你的主KEY名称

 

第二种方式：直接通过XCODE特性来配置（非常简单）

1>选择工程配置中的tages>capabilities页面

2>打开Keychain Sharing开关，设置你的主KEY的名称。

  LSF.iceTearsTest  是另外一个APP的entitlements file 

      LSF.Bluetooth  是当前项目的 entitlements file 

相互关联之后就可以通过不同的APP来 改变Keychain里边存储的数据





#import <Foundation/Foundation.h>

@interface ZFYKeychain : NSObject

/**

 *    @brief    存储密码

 *

 *    @param     password     密码内容

 *

 *    @param     key     键

 */

+(void)savePassWord:(NSString *)password forKey:(NSString *)key;

/**

 *    @brief    读取密码

 *

 *    @return    密码内容

 *

 *    @param     key     键

 */

+(id)readPassWordObjectForKey:(NSString *)key;

/**

 *    @brief    删除密码数据

 *

 *    @param     key     键

 */

+(void)deletePassWordObjectForKey:(NSString *)key;

@end

 

 

#import "ZFYKeychain.h"

@implementation ZFYKeychain

static NSString * const KEY_IN_KEYCHAIN = @"com.ZFYKeychain";//key 用来作为存取的标示

+(void)savePassWord:(NSString *)password forKey:(NSString *)key

{

    NSMutableDictionary *usernamepasswordKVPairs = [NSMutableDictionary dictionary];

    [usernamepasswordKVPairs setObject:password forKey:key];

    [self save:KEY_IN_KEYCHAIN data:usernamepasswordKVPairs];

}

+(id)readPassWordObjectForKey:(NSString *)key

{

    NSMutableDictionary *usernamepasswordKVPair = (NSMutableDictionary *)[self load:KEY_IN_KEYCHAIN];

    return [usernamepasswordKVPair objectForKey:key];

}

+(void)deletePassWordObjectForKey:(NSString *)key

{

    [self delete:key];

}

+ (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);

}