How to append data to NSKeyedArchive?

Question

I'm reading a file like so:

NSData *data = [NSData dataWithContentsOfFile:myPath];

NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:data];


NSData *imgData = [unarchiver decodeObjectForKey:@"myimage"];

if (imgData != nil) {
    self.image = [[NSImage alloc]initWithData:imgData];
}else{
    self.image = nil;
}

[unarchiver finishDecoding];
[unarchiver release];

What I'd like to do is to append image data for key @"myimage" to the same file if it doesn't exist.

How to go about it?

score 2 · Accepted Answer · answered Oct 07 '11 at 16:21

2

It seems that there's no way to "append" to NSKeyedArchive, so I just re-created it with the extra data added and have written over the original file.

answered Oct 07 '11 at 16:21

anna

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Yep. No methods provided for appending. If the data is large enough it may be worth using a good ol' unix FILE write/fwrite -- or using a DB. – wcochran Jul 22 '15 at 20:56

score -1 · Answer 2 · edited Sep 26 '12 at 06:39

-1

 NSString *archivePath = [NSTemporaryDirectory() stringByAppendingPathComponent:@"any name"];
[NSKeyedArchiver archiveRootObject:your object(example:singletonDataObjectref) toFile:archivePath];

edited Sep 26 '12 at 06:39

Jav_Rock

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answered Sep 17 '12 at 10:29

dhaya

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Quite apart that it would be good form to add some comment explaining your code, there is the minor detail that it *does not* address the question asked by the OP. – Marco Massenzio Feb 24 '16 at 06:37

How to append data to NSKeyedArchive?

2 Answers2

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