(C) Get Compressed ZIP Entry Data as Base64 Using ZipEntry.CopyToBase64

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This example creates a small ZIP archive containing a text file added from memory, writes the ZIP to disk, re-opens it, and then uses ZipEntry.CopyToBase64 to retrieve the compressed data for the text file as a Base64-encoded string.

The Base64 string returned by CopyToBase64 represents the compressed bytes stored for the entry inside the ZIP archive. It is not the original uncompressed text data.

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

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkZip zip;
    HCkZip zip2;
    HCkZipEntry entry;
    const char *b64;

    success = FALSE;

    // ------------------------------------------------------------
    // First create a sample ZIP archive containing a small text file.

    zip = CkZip_Create();

    success = CkZip_NewZip(zip,"c:/temp/sampleText.zip");
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        return;
    }

    // Add a small text file from memory.
    // The text is stored in the ZIP as "hello.txt".
    success = CkZip_AddString(zip,"hello.txt","Hello from a ZIP entry!","utf-8");
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        return;
    }

    // Write the ZIP archive to disk and close it.
    success = CkZip_WriteZipAndClose(zip);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        return;
    }

    // ------------------------------------------------------------
    // Now open the ZIP archive we just created.

    zip2 = CkZip_Create();

    success = CkZip_OpenZip(zip2,"c:/temp/sampleText.zip");
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip2));
        CkZip_Dispose(zip);
        CkZip_Dispose(zip2);
        return;
    }

    // Get the text file entry.
    entry = CkZipEntry_Create();

    success = CkZip_EntryOf(zip2,"hello.txt",entry);

    if (success == FALSE) {
        printf("Entry not found.\n");
        CkZip_Dispose(zip);
        CkZip_Dispose(zip2);
        CkZipEntry_Dispose(entry);
        return;
    }

    // Get the compressed ZIP entry data as Base64.
    // 
    // This is the compressed data stored inside the ZIP file,
    // not the uncompressed text "Hello from a ZIP entry!".
    b64 = CkZipEntry_copyToBase64(entry);

    printf("Base64 compressed ZIP entry data:\n");
    printf("%s\n",b64);

    CkZip_CloseZip(zip2);

    printf("Done.\n");


    CkZip_Dispose(zip);
    CkZip_Dispose(zip2);
    CkZipEntry_Dispose(entry);

    }