(Objective-C) Replacment for Deprecated Crypt2 Compress Functions

The Chilkat Crypt2 compression functions are deprecated and will be removed. This example shows how to duplicate the functionality using the Chilkat Compression class.

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#import <CkoCrypt2.h>
#import <CkoStringBuilder.h>
#import <NSString.h>
#import <CkoBinData.h>
#import <CkoCompression.h>

CkoCrypt2 *crypt = [[CkoCrypt2 alloc] init];

// Create data to be compressed.
CkoStringBuilder *sb = [[CkoStringBuilder alloc] init];
int i = 0;
while (i < 25) {
    [sb Append: @"Hello World, this is a test.\r\n"];
    i = i + 1;
}

// Bzip2 compress the utf-8 byte representation of the string and return the compressed data as base64.
crypt.Charset = @"utf-8";
crypt.EncodingMode = @"base64";
NSString *compressedStr = [crypt CompressStringENC: [sb GetAsString]];

NSLog(@"%@",compressedStr);

// Result: 4aeUs+4CAABCWmgzMUFZJlNZZ6znBgAAfNeAABJABQBAAIAmZJwAIABwUNNMAAUqoekYjMp4ixF1FlFxF8i5i1FvFwizF9iwi9RdxaizF7RZi6i0ixF3Fui/i7kinChIM9ZzgwA=

// The result contains an 8-byte header composed of a 4-byte magic number (0xB394A7E1) and a 4-byte length.
// Do the following to BZip2 decompress using Chilkat Compression
CkoBinData *bd = [[CkoBinData alloc] init];
[bd AppendEncoded: compressedStr encoding: @"base64"];

// Remove the 8-byte header.
[bd RemoveChunk: [NSNumber numberWithInt: 0] numBytes: [NSNumber numberWithInt: 8]];

// Decompress
CkoCompression *compress = [[CkoCompression alloc] init];
compress.Algorithm = @"bzip2";
[compress DecompressBd: bd];

// Get the decompressed string.
NSString *decompressedStr = [bd GetString: @"utf-8"];
NSLog(@"%@",decompressedStr);