C Requires Chilkat v11.0.0+

Find a ZIP Entry by EntryID Using EntryById

See more Zip Examples

This example demonstrates how to use the EntryById method to retrieve a ZIP entry using its unique EntryID.

Each ZipEntry object has an EntryID property that uniquely identifies the entry within the currently open ZIP object.

This is useful when:

• An application stores EntryID values for later use
• ZIP entries need to be retrieved without searching by filename
• Multiple entries may have similar names or paths

The example:

• Opens a ZIP archive
• Retrieves an entry using EntryAt
• Saves the entry's EntryID
• Uses EntryById to retrieve the same entry later

C

#include <C_CkZip.h>
#include <C_CkZipEntry.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkZip zip;
    HCkZipEntry entry;
    int entryId;
    HCkZipEntry entry2;

    success = FALSE;

    //  Open an existing ZIP archive.
    zip = CkZip_Create();

    success = CkZip_OpenZip(zip,"example.zip");
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        return;
    }

    //  Retrieve the first entry in the ZIP archive.
    entry = CkZipEntry_Create();

    success = CkZip_EntryAt(zip,0,entry);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        CkZipEntry_Dispose(entry);
        return;
    }

    printf("Original entry:\n");
    printf("  FileName: %s\n",CkZipEntry_fileName(entry));
    printf("  EntryID: %d\n",CkZipEntry_getEntryID(entry));
    printf("\n");

    //  Save the EntryID for later use.
    entryId = CkZipEntry_getEntryID(entry);

    //  Create another ZipEntry object.
    entry2 = CkZipEntry_Create();

    //  Retrieve the same entry using EntryById.
    success = CkZip_EntryById(zip,entryId,entry2);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        CkZipEntry_Dispose(entry);
        CkZipEntry_Dispose(entry2);
        return;
    }

    printf("Entry retrieved by EntryID:\n");
    printf("  FileName: %s\n",CkZipEntry_fileName(entry2));
    printf("  EntryID: %d\n",CkZipEntry_getEntryID(entry2));
    printf("\n");

    //  The filenames and EntryID values should match.
    CkZip_CloseZip(zip);

    printf("Done.\n");


    CkZip_Dispose(zip);
    CkZipEntry_Dispose(entry);
    CkZipEntry_Dispose(entry2);

    }