iOS中利用KeyChain保存用户信息的方法示例

2020-07-26 02:46:32

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前言

说到保存用户名和密码，以前有用过本地的数据库来保存，也接触过用userdefault来保存，后来在一个项目中发现了一个新的方法――用Keychain来保存。下面话不多说了，直接通过示例代码来介绍吧。

方法示例

一、新建一个LYKeychainTool类，导入系统Security框架，LYKeychainTool.h文件实现如下：

//// LYKeychainTool.h// keyChainTest//// Created by Liyu on 2017/6/2.// Copyright © 2017年 liyu. All rights reserved.//#import <Foundation/Foundation.h>#import <Security/Security.h>@interface LYKeychainTool : NSObject/** * 储存字符串到钥匙串 * @param sValue 对应的Value * @param sKey 对应的Key */+ (void)saveKeychainValue:(NSString *)sValue key:(NSString *)sKey;/** * 从钥匙串获取字符串 * @param sKey 对应的Key * @return 返回储存的Value */+ (NSString *)readKeychainValue:(NSString *)sKey;/** * 从钥匙串删除字符串 * @param sKey 对应的Key */+ (void)deleteKeychainValue:(NSString *)sKey;@end

二、LYKeychainTool.m文件实现如下：

//// LYKeychainTool.m// keyChainTest//// Created by Liyu on 2017/6/2.// Copyright © 2017年 liyu. All rights reserved.//#import "LYKeychainTool.h"@implementation LYKeychainTool+ (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:(NSString *)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);}+ (NSString *)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

三、ViewController 调用

//// ViewController.m// keyChainTest//// Created by Liyu on 2017/6/2.// Copyright © 2017年 liyu. All rights reserved.//#import "ViewController.h"#import "LYKeychainTool.h"@interface ViewController ()@property (weak, nonatomic) IBOutlet UITextField *userNameTextField;@property (weak, nonatomic) IBOutlet UITextField *passwordTextField;@end@implementation ViewController- (void)viewDidLoad { [super viewDidLoad];}- (IBAction)saveBtn:(id)sender { [LYKeychainTool saveKeychainValue:self.userNameTextField.text key:@"userName"]; [LYKeychainTool saveKeychainValue:self.passwordTextField.text key:@"password"];}- (IBAction)readeBtn:(id)sender { self.userNameTextField.text = [NSString stringWithFormat:@"读取到用户名:%@",[LYKeychainTool readKeychainValue:@"userName"]]; self.passwordTextField.text = [NSString stringWithFormat:@"读取到用户密码:%@",[LYKeychainTool readKeychainValue:@"password"]];}- (IBAction)deleteBtn:(id)sender { [LYKeychainTool deleteKeychainValue:@"userName"]; [LYKeychainTool deleteKeychainValue:@"password"];}- (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning];}@end

四、效果如下图：