我可以访问iPhone上的钥匙扣吗?

还有一点需要注意:当使用旧版本(2.x,3.x)的iPhone SDK时,钥匙链API在模拟器中不起作用。这可以在测试时为您节省很多沮丧!

你可以使用一个钥匙链——对于代码,最好的办法是查看苹果公司的GenericKeychain示例应用程序:

GenericKeychain sample

我真的很喜欢 Buzz Anderson's Keychain abstraction layer 我热切地等待着 Jens Alfke's MYCrypto 以达到可用状态。后者在允许在Mac OS X和iPhone上使用相同的代码方面做得很好,尽管它的功能只模仿了Keychain的一小部分。

以下是我在钥匙链中存储键/值对的方法。确保将Security.framework添加到您的项目中

#import <Security/Security.h>

// -------------------------------------------------------------------------
-(NSString *)getSecureValueForKey:(NSString *)key {
    /*

     Return a value from the keychain

     */

    // Retrieve a value from the keychain
    NSDictionary *result;
    NSArray *keys = [[[NSArray alloc] initWithObjects: (NSString *) kSecClass, kSecAttrAccount, kSecReturnAttributes, nil] autorelease];
    NSArray *objects = [[[NSArray alloc] initWithObjects: (NSString *) kSecClassGenericPassword, key, kCFBooleanTrue, nil] autorelease];
    NSDictionary *query = [[NSDictionary alloc] initWithObjects: objects forKeys: keys];

    // Check if the value was found
    OSStatus status = SecItemCopyMatching((CFDictionaryRef) query, (CFTypeRef *) &result);
    [query release];
    if (status != noErr) {
        // Value not found
        return nil;
    } else {
        // Value was found so return it
        NSString *value = (NSString *) [result objectForKey: (NSString *) kSecAttrGeneric];
        return value;
    }
}




// -------------------------------------------------------------------------
-(bool)storeSecureValue:(NSString *)value forKey:(NSString *)key {
    /*

     Store a value in the keychain

     */

    // Get the existing value for the key
    NSString *existingValue = [self getSecureValueForKey:key];

    // Check if a value already exists for this key
    OSStatus status;
    if (existingValue) {
        // Value already exists, so update it
        NSArray *keys = [[[NSArray alloc] initWithObjects: (NSString *) kSecClass, kSecAttrAccount, nil] autorelease];
        NSArray *objects = [[[NSArray alloc] initWithObjects: (NSString *) kSecClassGenericPassword, key, nil] autorelease];
        NSDictionary *query = [[[NSDictionary alloc] initWithObjects: objects forKeys: keys] autorelease];
        status = SecItemUpdate((CFDictionaryRef) query, (CFDictionaryRef) [NSDictionary dictionaryWithObject:value forKey: (NSString *) kSecAttrGeneric]);
    } else {
        // Value does not exist, so add it
        NSArray *keys = [[[NSArray alloc] initWithObjects: (NSString *) kSecClass, kSecAttrAccount, kSecAttrGeneric, nil] autorelease];
        NSArray *objects = [[[NSArray alloc] initWithObjects: (NSString *) kSecClassGenericPassword, key, value, nil] autorelease];
        NSDictionary *query = [[[NSDictionary alloc] initWithObjects: objects forKeys: keys] autorelease];
        status = SecItemAdd((CFDictionaryRef) query, NULL);
    }

    // Check if the value was stored
    if (status != noErr) {
        // Value was not stored
        return false;
    } else {
        // Value was stored
        return true;
    }
}

值得注意的是,如果用户删除您的应用程序,这些键/值将不会被删除。如果用户删除了您的应用程序,然后重新安装,则键/值仍然可以访问。

还要记住,在生成AppID时,如果您希望多个应用程序访问相同的钥匙串信息,则必须生成通配符AppID(######.com.preform.*)。..

在GenericKeychain示例的最新版本1.2中,苹果提供了一个也在iPhone模拟器上运行的钥匙链包装器。查看这篇文章了解详细信息: http://dev-metal.blogspot.com/2010/08/howto-use-keychain-in-iphone-sdk-to.html

这是Granoff先生提供的另一个很好的包装类 https://github.com/granoff/Lockbox 谢谢