Objective-C

Remove an Entry from an Existing ZIP Using DeleteEntry

See more Zip Examples

This example demonstrates how to use the DeleteEntry method to remove a file from an existing ZIP archive.

The example:

• Creates a ZIP archive containing three text files
• Opens the ZIP archive for modification
• Finds and deletes one entry
• Writes the modified ZIP archive to a new filename

Suppose the original ZIP archive contains:

a.txt
b.txt
c.txt

After deleting b.txt, the modified ZIP archive contains:

a.txt
c.txt

The entry is removed only from the in-memory ZIP object until a Write* method is called.

Objective-C

#import <CkoZip.h>
#import <NSString.h>
#import <CkoZipEntry.h>

BOOL success = NO;

//  ------------------------------------------------------------
//  First create a ZIP archive containing three text files.

CkoZip *zip = [[CkoZip alloc] init];

success = [zip NewZip: @"original.zip"];
if (success == NO) {
    NSLog(@"%@",zip.LastErrorText);
    return;
}

NSString *charset = @"utf-8";

success = [zip AddString: @"a.txt" content: @"Contents of file A" charset: charset];
if (success == NO) {
    NSLog(@"%@",zip.LastErrorText);
    return;
}

success = [zip AddString: @"b.txt" content: @"Contents of file B" charset: charset];
if (success == NO) {
    NSLog(@"%@",zip.LastErrorText);
    return;
}

success = [zip AddString: @"c.txt" content: @"Contents of file C" charset: charset];
if (success == NO) {
    NSLog(@"%@",zip.LastErrorText);
    return;
}

//  Write the ZIP archive to disk.
//  
//  The ZIP now contains:
//  
//      a.txt
//      b.txt
//      c.txt
//  
success = [zip WriteZipAndClose];
if (success == NO) {
    NSLog(@"%@",zip.LastErrorText);
    return;
}

//  ------------------------------------------------------------
//  Open the existing ZIP archive for modification.

CkoZip *zip2 = [[CkoZip alloc] init];

success = [zip2 OpenZip: @"original.zip"];
if (success == NO) {
    NSLog(@"%@",zip2.LastErrorText);
    return;
}

//  Find the entry named "b.txt".
CkoZipEntry *entry = [[CkoZipEntry alloc] init];

success = [zip2 EntryOf: @"b.txt" entry: entry];
if (success == NO) {
    NSLog(@"%@",zip2.LastErrorText);
    return;
}

//  Remove the entry from the in-memory ZIP object.
//  
//  At this point, the original ZIP file on disk is unchanged.
//  The deletion takes effect only after WriteZip or
//  WriteZipAndClose is called.
success = [zip2 DeleteEntry: entry];
if (success == NO) {
    NSLog(@"%@",zip2.LastErrorText);
    return;
}

//  Write the modified ZIP archive to a new file.
zip2.FileName = @"modified.zip";

success = [zip2 WriteZipAndClose];
if (success == NO) {
    NSLog(@"%@",zip2.LastErrorText);
    return;
}

//  The modified ZIP now contains:
//  
//      a.txt
//      c.txt
//  

NSLog(@"%@",@"ZIP archive updated successfully.");