Objective c 是否将NSMutableArray对象保存/写入磁盘？

起初我以为这会起作用，但现在我明白了，这不会起作用，因为artistCollection是一个由“艺术家”对象组成的NSMutableArray

我的问题是，将NSMutableArray中的“艺术家”对象录制到磁盘，以便下次运行应用程序时加载它们的最佳方式是什么

artistCollection = [[NSMutableArray alloc] init];

newArtist = [[Artist alloc] init];
[newArtist setFirName:objFirName];
[newArtist setSurName:objSurName];
[artistCollection addObject:newArtist];

NSLog(@"(*) - Save All");
[artistCollection writeToFile:@"/Users/Fgx/Desktop/stuff.txt" atomically:YES];

编辑 非常感谢，最后一件事我很好奇。如果“Artister”包含更多对象（应用程序）的NSMutableArray（softwareOwned）的额外实例变量，我将如何扩展编码以涵盖这一点？我会将NSCoding添加到“Applications”对象中，然后在编码“Artist”之前对其进行编码，还是有办法在“Artist”中指定这一点

非常感谢

---

gary

看看NSKeyedArchiver。简而言之：

NSData* artistData = [NSKeyedArchiver archivedDataWithRootObject:artistCollection];
[artistData writeToFile: @"/Users/Fgx/Desktop/stuff" atomically:YES];

您需要在Artist类上实现encodeWithCoder:请参见

---

未归档（请参见NSKeyedUnarchiver）留给读者作为练习：）

writeToFile:atomicaly:

在Cocoa的集合类中仅适用于属性列表，即仅适用于包含标准对象（如NSString、NSNumber、其他集合等）的集合

要详细说明，如果集合包含的所有对象都可以自行存档，则可以使用

NSKeyedArchiver

存档集合。要为自定义类实现此功能，请使其符合

NSCoding

协议：

@interface Artist : NSObject <NSCoding> {
    NSString *firName;
    NSString *surName;
}

@end


@implementation Artist

static NSString *FirstNameArchiveKey = @"firstName";
static NSString *LastNameArchiveKey = @"lastName";

- (id)initWithCoder:(NSCoder *)decoder {
    self = [super init];
    if (self != nil) {
        firName = [[decoder decodeObjectForKey:FirstNameArchiveKey] retain];
        surName = [[decoder decodeObjectForKey:LastNameArchiveKey] retain];
    }
    return self;
}   

- (void)encodeWithCoder:(NSCoder *)encoder {
    [encoder encodeObject:firName forKey:FirstNameArchiveKey];
    [encoder encodeObject:surName forKey:LastNameArchiveKey];
}

@end

---

要回答您的编辑：只需为您的应用程序类实现NSCoding，并在Artist's encodeWithCoder:和initWithCoder:中添加行来处理可变数组的编码/解码。当要求对自身进行编码时，数组将要求应用程序对象对自身进行编码。啊，我明白了，很好，谢谢。

NSData* artistData = [NSKeyedArchiver archivedDataWithRootObject:artistCollection];
[artistData writeToFile: @"/Users/Fgx/Desktop/stuff" atomically:YES];

@interface Artist : NSObject <NSCoding> {
    NSString *firName;
    NSString *surName;
}

@end


@implementation Artist

static NSString *FirstNameArchiveKey = @"firstName";
static NSString *LastNameArchiveKey = @"lastName";

- (id)initWithCoder:(NSCoder *)decoder {
    self = [super init];
    if (self != nil) {
        firName = [[decoder decodeObjectForKey:FirstNameArchiveKey] retain];
        surName = [[decoder decodeObjectForKey:LastNameArchiveKey] retain];
    }
    return self;
}   

- (void)encodeWithCoder:(NSCoder *)encoder {
    [encoder encodeObject:firName forKey:FirstNameArchiveKey];
    [encoder encodeObject:surName forKey:LastNameArchiveKey];
}

@end

NSData* artistData = [NSKeyedArchiver archivedDataWithRootObject:artistCollection];
[artistData writeToFile: @"/Users/Fgx/Desktop/stuff" atomically:YES];