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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#import @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：
总结
以上就是这篇文章的全部内容了，希望本文的内容对大家的学习或者工作能带来一定的帮助，如果有疑问大家可以留言交流，谢谢大家对创新互联的支持。
