(Objective-C) Compress and Decompress Base64

Imagine we have data represented as a base64 string. This example demonstrates how to decode, compress, and re-encode to smaller base64 representing the compressed data.

Note: This example requires Chilkat v9.5.0.66 or greater.

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

// This example assumes the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

BOOL success;

NSString *strBase64 = @"VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NClRoZSBxdWljayBicm93biBmb3gganVtcGVkIG92ZXIgdGhlIGxhenkgZG9nLg0KVGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NCg0K";

CkoCompression *compress = [[CkoCompression alloc] init];
compress.Algorithm = @"deflate";

CkoBinData *binDat = [[CkoBinData alloc] init];
// Load the base64 data into a BinData object.
// This decodes the base64. The decoded bytes will be contained in the BinData.
[binDat AppendEncoded: strBase64 encoding: @"base64"];

// Compress the BinData.
[compress CompressBd: binDat];

// Get the compressed data in base64 format:
NSString *compressedBase64 = [binDat GetEncoded: @"base64"];
NSLog(@"%@",@"compressed base64:");
NSLog(@"%@",compressedBase64);

// The compressed base64 is: C8lIVSgszUzOVkgqyi/PU0jLr1DIKs0tSE1RyC9LLVIoAcrnJFZVKqTkp+vxcoUMYeW8XAA=

// Now decompress:
[binDat Clear];
[binDat AppendEncoded: compressedBase64 encoding: @"base64"];
[compress DecompressBd: binDat];

NSString *decompressedBase64 = [binDat GetEncoded: @"base64"];
NSLog(@"%@",@"decompressed base64:");
NSLog(@"%@",decompressedBase64);

// The output is the original data:
// VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NClRoZSBxdWljayBicm93biBmb3gganVtcGVkIG92ZXIgdGhlIGxhenkgZG9nLg0KVGhlIHF1aWNrIGJyb3duIGZveCBqdW1wZWQgb3ZlciB0aGUgbGF6eSBkb2cuDQpUaGUgcXVpY2sgYnJvd24gZm94IGp1bXBlZCBvdmVyIHRoZSBsYXp5IGRvZy4NCg0K