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Objective-C

Replace/Update a FIle in a .zip

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Demonstrates how to replace/update a file from a .zip. Note: This requires the entire .zip to be rewritten.

Chilkat Objective-C Downloads

Objective-C
#import <CkoZip.h>
#import <NSString.h>
#import <CkoZipEntry.h>

BOOL success = NO;

// This requires the Chilkat Zip API to have been previously unlocked.
// See Unlock Chilkat Zip for sample code.

// First prepare a .zip and write it..
CkoZip *zip = [[CkoZip alloc] init];

[zip NewZip: @"qa_output/abc.zip"];

// Add some files..
NSString *charset = @"utf-8";
[zip AddString: @"a.txt" content: @"aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" charset: charset];
[zip AddString: @"b.txt" content: @"bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb" charset: charset];
[zip AddString: @"c.txt" content: @"cccccccccccccccccccccccccccccccccccc" charset: charset];

// Write to qa_output/abc.zip
// This .zip contains three files: a.txt, b.txt, and c.txt
success = [zip WriteZipAndClose];

// -------------------------------------------------------------------
// Open abc.zip, replace the content of the "b.txt" entry with something else, and re-write.
CkoZip *zip2 = [[CkoZip alloc] init];
[zip2 OpenZip: @"qa_output/abc.zip"];

CkoZipEntry *entry = [[CkoZipEntry alloc] init];
if ([zip2 EntryOf: @"b.txt" entry: entry] == YES) {
    [entry ReplaceString: @"This is the new content.  bbbbbbbbbbbbbbbbbbbbbb" charset: @"utf-8"];
}

// Write the modified .zip back to "abc.zip"
success = [zip2 WriteZipAndClose];

NSLog(@"%@",@"success.");