Swift

Unzip a ZIP Entry Directly into a BinData Object Using ZipEntry.UnzipToBd

See more Zip Examples

This example demonstrates how to use the ZipEntry.UnzipToBd method to inflate a ZIP entry directly into a BinData object.

The entry contents are uncompressed entirely in memory without creating a file on disk.

This is useful when:

• Processing ZIP entry data entirely in memory
• Avoiding temporary filesystem files
• Working with binary files such as images, PDFs, or certificates
• Passing uncompressed ZIP data directly to other APIs

The example opens a ZIP archive, locates a PDF entry, inflates it into a BinData object, and then writes the uncompressed bytes to a new file.

Suppose the ZIP archive contains:

docs/report.pdf

The entry is uncompressed directly into memory before optionally being saved to:

qa_output/report.pdf

Swift

func chilkatTest() {
    var success: Bool = false

    let zip = CkoZip()!

    // Open an existing ZIP archive.
    success = zip.open(zipPath: "qa_data/zips/documents.zip")
    if success == false {
        print("\(zip.lastErrorText!)")
        return
    }

    // Locate the PDF entry within the ZIP archive.
    let entry = CkoZipEntry()!

    success = zip.entry(of: "docs/report.pdf", entry: entry)
    if success == false {
        print("ZIP entry not found.")
        zip.close()
        return
    }

    // ------------------------------------------------------------
    // Inflate the ZIP entry directly into a BinData object.
    // 
    // The uncompressed bytes are stored entirely in memory.
    // 
    let pdfData = CkoBinData()!

    success = entry.unzip(toBd: pdfData)
    if success == false {
        print("\(entry.lastErrorText!)")
        return
    }

    print("Uncompressed size = \(pdfData.numBytes.intValue)")
    print("")

    // ------------------------------------------------------------
    // Optionally save the uncompressed bytes to a file.
    // 
    success = pdfData.writeFile(path: "qa_output/report.pdf")
    if success == false {
        print("\(pdfData.lastErrorText!)")
        return
    }

    zip.close()

    print("PDF extracted successfully.")

}