(C++) Remove an Entry from an Existing ZIP Using DeleteEntry

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.

Note: This example requires Chilkat v11.0.0 or greater.

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#include <CkZip.h>
#include <CkZipEntry.h>

void ChilkatSample(void)
    {
    bool success = false;

    success = false;

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

    CkZip zip;

    success = zip.NewZip("original.zip");
    if (success == false) {
        std::cout << zip.lastErrorText() << "\r\n";
        return;
    }

    const char *charset = "utf-8";

    success = zip.AddString("a.txt","Contents of file A",charset);
    if (success == false) {
        std::cout << zip.lastErrorText() << "\r\n";
        return;
    }

    success = zip.AddString("b.txt","Contents of file B",charset);
    if (success == false) {
        std::cout << zip.lastErrorText() << "\r\n";
        return;
    }

    success = zip.AddString("c.txt","Contents of file C",charset);
    if (success == false) {
        std::cout << zip.lastErrorText() << "\r\n";
        return;
    }

    // Write the ZIP archive to disk.
    // 
    // The ZIP now contains:
    // 
    //     a.txt
    //     b.txt
    //     c.txt
    // 
    success = zip.WriteZipAndClose();
    if (success == false) {
        std::cout << zip.lastErrorText() << "\r\n";
        return;
    }

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

    CkZip zip2;

    success = zip2.OpenZip("original.zip");
    if (success == false) {
        std::cout << zip2.lastErrorText() << "\r\n";
        return;
    }

    // Find the entry named "b.txt".
    CkZipEntry entry;

    success = zip2.EntryOf("b.txt",entry);
    if (success == false) {
        std::cout << zip2.lastErrorText() << "\r\n";
        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 == false) {
        std::cout << zip2.lastErrorText() << "\r\n";
        return;
    }

    // Write the modified ZIP archive to a new file.
    zip2.put_FileName("modified.zip");

    success = zip2.WriteZipAndClose();
    if (success == false) {
        std::cout << zip2.lastErrorText() << "\r\n";
        return;
    }

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

    std::cout << "ZIP archive updated successfully." << "\r\n";
    }