iOS keychain存储数据

iOS存储数据一般在删除APP之后，所有数据就都跟着没有了，但是iOS也提供了一个可以在删除APP之后，数据还在的保存方式，那就是keychain存储

具体使用如下：

iOS存储数据一般在删除APP之后，所有数据就都跟着没有了，但是iOS也提供了一个可以在删除APP之后，数据还在的保存方式，那就是keychain存储

具体使用如下：

#import <Foundation/Foundation.h>

@interface YFKeychainTool : NSObject

  // 储存字符串到钥匙串

+ (void)saveKeychainValue:(id)sValue key:(NSString *)sKey;

  //从钥匙串获取字符串

+ (id)readKeychainValue:(NSString *)sKey;

 //从钥匙串删除字符串

+ (void)deleteKeychainValue:(NSString *)sKey;

@end

#import "YFKeychainTool.h"

@implementation YFKeychainTool

+ (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)saveKeychainValue:(id)sValue key:(NSString *)sKey{

    NSMutableDictionary * keychainQuery = [self getKeychainQuery:sKey];

    SecItemDelete((__bridge_retained CFDictionaryRef)keychainQuery);

    

    [keychainQuery setObject:[NSKeyedArchiver archivedDataWithRootObject:sValue] forKey:(__bridge_transfer id)kSecValueData];

    

    SecItemAdd((__bridge_retained CFDictionaryRef)keychainQuery, NULL);

    

}

+ (id)readKeychainValue:(NSString *)sKey

{

    NSString *ret = nil;

    NSMutableDictionary *keychainQuery = [self getKeychainQuery:sKey];

    [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 CFDictionaryRef)keychainQuery, (CFTypeRef *)&keyData) == noErr) {

        @try {

            ret = (NSString *)[NSKeyedUnarchiver unarchiveObjectWithData:(__bridge NSData *)keyData];

        } @catch (NSException *e) {

            NSLog(@"Unarchive of %@ failed: %@", sKey, e);

        } @finally {

        }

    }

    if (keyData)

        CFRelease(keyData);

    return ret;

}

+ (void)deleteKeychainValue:(NSString *)sKey {

    NSMutableDictionary *keychainQuery = [self getKeychainQuery:sKey];

    SecItemDelete((__bridge CFDictionaryRef)keychainQuery);

}

@end