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

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

    success = FALSE;

    success = FALSE;

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

    zip = CkZip_Create();

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

    charset = "utf-8";

    success = CkZip_AddString(zip,"a.txt","Contents of file A",charset);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        return;
    }

    success = CkZip_AddString(zip,"b.txt","Contents of file B",charset);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        return;
    }

    success = CkZip_AddString(zip,"c.txt","Contents of file C",charset);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        return;
    }

    // Write the ZIP archive to disk.
    // 
    // The ZIP now contains:
    // 
    //     a.txt
    //     b.txt
    //     c.txt
    // 
    success = CkZip_WriteZipAndClose(zip);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        return;
    }

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

    zip2 = CkZip_Create();

    success = CkZip_OpenZip(zip2,"original.zip");
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip2));
        CkZip_Dispose(zip);
        CkZip_Dispose(zip2);
        return;
    }

    // Find the entry named "b.txt".
    entry = CkZipEntry_Create();

    success = CkZip_EntryOf(zip2,"b.txt",entry);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip2));
        CkZip_Dispose(zip);
        CkZip_Dispose(zip2);
        CkZipEntry_Dispose(entry);
        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 = CkZip_DeleteEntry(zip2,entry);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip2));
        CkZip_Dispose(zip);
        CkZip_Dispose(zip2);
        CkZipEntry_Dispose(entry);
        return;
    }

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

    success = CkZip_WriteZipAndClose(zip2);
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip2));
        CkZip_Dispose(zip);
        CkZip_Dispose(zip2);
        CkZipEntry_Dispose(entry);
        return;
    }

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

    printf("ZIP archive updated successfully.\n");


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

    }