iOS中利用KeyChain保存用戶信息的方法示例

2020-07-26 02:46:32

字體：大中小

來源：轉載

供稿：網友

前言

說到保存用戶名和密碼，以前有用過本地的數據庫來保存，也接觸過用userdefault來保存，后來在一個項目中發現了一個新的方法――用Keychain來保存。下面話不多說了，直接通過示例代碼來介紹吧。

方法示例

一、新建一個LYKeychainTool類，導入系統Security框架，LYKeychainTool.h文件實現如下：

//// 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/** * 儲存字符串到鑰匙串 * @param sValue 對應的Value * @param sKey 對應的Key */+ (void)saveKeychainValue:(NSString *)sValue key:(NSString *)sKey;/** * 從鑰匙串獲取字符串 * @param sKey 對應的Key * @return 返回儲存的Value */+ (NSString *)readKeychainValue:(NSString *)sKey;/** * 從鑰匙串刪除字符串 * @param sKey 對應的Key */+ (void)deleteKeychainValue:(NSString *)sKey;@end

二、LYKeychainTool.m文件實現如下：

//// 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 調用

//// 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:@"讀取到用戶名:%@",[LYKeychainTool readKeychainValue:@"userName"]]; self.passwordTextField.text = [NSString stringWithFormat:@"讀取到用戶密碼:%@",[LYKeychainTool readKeychainValue:@"password"]];}- (IBAction)deleteBtn:(id)sender { [LYKeychainTool deleteKeychainValue:@"userName"]; [LYKeychainTool deleteKeychainValue:@"password"];}- (void)didReceiveMemoryWarning { [super didReceiveMemoryWarning];}@end

四、效果如下圖：