iOS/Iphone如何清除keychain

参见链接：

http://stackoverflow.com/questions/7142774/reset-an-iphone-apps-keychain

代码：

-(void)resetKeychain {
    [self deleteAllKeysForSecClass:kSecClassGenericPassword];
    [self deleteAllKeysForSecClass:kSecClassInternetPassword];
    [self deleteAllKeysForSecClass:kSecClassCertificate];
    [self deleteAllKeysForSecClass:kSecClassKey];
    [self deleteAllKeysForSecClass:kSecClassIdentity];
}

-(void)deleteAllKeysForSecClass:(CFTypeRef)secClass {
    NSMutableDictionary* dict = [NSMutableDictionary dictionary];
    [dict setObject:(__bridge id)secClass forKey:(__bridge id)kSecClass];
    OSStatus result = SecItemDelete((__bridge CFDictionaryRef) dict);
    NSAssert(result == noErr || result == errSecItemNotFound, @"Error deleting keychain data (%ld)", result);
}