Go

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

Go

    success := false

    zip := chilkat.NewZip()

    // Open an existing ZIP archive.
    success = zip.OpenZip("qa_data/zips/documents.zip")
    if success == false {
        fmt.Println(zip.LastErrorText())
        zip.DisposeZip()
        return
    }

    // Locate the PDF entry within the ZIP archive.
    entry := chilkat.NewZipEntry()

    success = zip.EntryOf("docs/report.pdf",entry)
    if success == false {
        fmt.Println("ZIP entry not found.")
        zip.CloseZip()
        zip.DisposeZip()
        entry.DisposeZipEntry()
        return
    }

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

    success = entry.UnzipToBd(pdfData)
    if success == false {
        fmt.Println(entry.LastErrorText())
        zip.DisposeZip()
        entry.DisposeZipEntry()
        pdfData.DisposeBinData()
        return
    }

    fmt.Println("Uncompressed size = ", pdfData.NumBytes())
    fmt.Println("")

    // ------------------------------------------------------------
    // Optionally save the uncompressed bytes to a file.
    // 
    success = pdfData.WriteFile("qa_output/report.pdf")
    if success == false {
        fmt.Println(pdfData.LastErrorText())
        zip.DisposeZip()
        entry.DisposeZipEntry()
        pdfData.DisposeBinData()
        return
    }

    zip.CloseZip()

    fmt.Println("PDF extracted successfully.")

    zip.DisposeZip()
    entry.DisposeZipEntry()
    pdfData.DisposeBinData()