- (instancetype)initWithCoder:(NSCoder *)aDecoder
{
    NSLog(@"initWithCoder");

    self = [super init];
    if (self)
    {
        self.textInput = [aDecoder decodeObjectForKey:@"textInput"];
    }

    return self;
}

- (void)encodeWithCoder:(NSCoder *)aCoder
{
    NSLog(@"encode");

    [aCoder encodeObject:textInput forKey:@"textInput"];
}

// 编码
CodingObject *codingObject = [[CodingObject alloc] init];
codingObject.textInput = @"编码与解码";
NSData *object = [NSKeyedArchiver archivedDataWithRootObject:codingObject];

// 解码
CodingObject *codingObject = [NSKeyedUnarchiver unarchiveObjectWithData:data];