C

Unzip a Text File Entry into a StringBuilder Using ZipEntry.UnzipToSb

See more Zip Examples

This example demonstrates how to use the ZipEntry.UnzipToSb method to inflate a text file entry directly into a StringBuilder object.

The ZIP entry is uncompressed entirely in memory and appended to the StringBuilder without creating a temporary file on disk.

This is useful when:

• Processing text files directly in memory
• Avoiding temporary filesystem files
• Reading configuration files, JSON, XML, CSV, or source code from ZIP archives
• Automatically converting line endings while inflating the text

The srcCharset argument specifies how the uncompressed bytes should be interpreted, such as:

• utf-8
• utf-16
• windows-1252

The lineEndingBehavior argument controls line-ending conversion:

• 0 — Leave line endings unchanged
• 1 — Convert all line endings to bare LF
• 2 — Convert all line endings to CRLF

Suppose the ZIP archive contains:

config/settings.json

The example inflates the JSON file directly into a StringBuilder.

C

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

void ChilkatSample(void)
    {
    BOOL success;
    HCkZip zip;
    HCkZipEntry entry;
    HCkStringBuilder sb;
    int lineEndingBehavior;
    const char *srcCharset;

    success = FALSE;

    zip = CkZip_Create();

    // Open an existing ZIP archive.
    success = CkZip_OpenZip(zip,"qa_data/zips/configFiles.zip");
    if (success == FALSE) {
        printf("%s\n",CkZip_lastErrorText(zip));
        CkZip_Dispose(zip);
        return;
    }

    // Locate the JSON file entry within the ZIP archive.
    entry = CkZipEntry_Create();

    success = CkZip_EntryOf(zip,"config/settings.json",entry);
    if (success == FALSE) {
        printf("ZIP entry not found.\n");
        CkZip_CloseZip(zip);
        CkZip_Dispose(zip);
        CkZipEntry_Dispose(entry);
        return;
    }

    // ------------------------------------------------------------
    // Inflate the ZIP entry directly into a StringBuilder.
    // 
    // The uncompressed text is appended to the StringBuilder.
    // 
    sb = CkStringBuilder_Create();

    // Leave line endings unchanged.
    lineEndingBehavior = 0;

    // Interpret the uncompressed bytes as UTF-8 text.
    srcCharset = "utf-8";

    success = CkZipEntry_UnzipToSb(entry,lineEndingBehavior,srcCharset,sb);
    if (success == FALSE) {
        printf("%s\n",CkZipEntry_lastErrorText(entry));
        CkZip_Dispose(zip);
        CkZipEntry_Dispose(entry);
        CkStringBuilder_Dispose(sb);
        return;
    }

    printf("Uncompressed text:\n");
    printf("\n");
    printf("%s\n",CkStringBuilder_getAsString(sb));

    CkZip_CloseZip(zip);

    printf("Done.\n");


    CkZip_Dispose(zip);
    CkZipEntry_Dispose(entry);
    CkStringBuilder_Dispose(sb);

    }