SQL Server

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

SQL Server

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    DECLARE @iTmp0 int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @success int
    SELECT @success = 0

    DECLARE @zip int
    EXEC @hr = sp_OACreate 'Chilkat.Zip', @zip OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- Open an existing ZIP archive.
    EXEC sp_OAMethod @zip, 'OpenZip', @success OUT, 'qa_data/zips/documents.zip'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @zip, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @zip
        RETURN
      END

    -- Locate the PDF entry within the ZIP archive.
    DECLARE @entry int
    EXEC @hr = sp_OACreate 'Chilkat.ZipEntry', @entry OUT

    EXEC sp_OAMethod @zip, 'EntryOf', @success OUT, 'docs/report.pdf', @entry
    IF @success = 0
      BEGIN

        PRINT 'ZIP entry not found.'
        EXEC sp_OAMethod @zip, 'CloseZip', NULL
        EXEC @hr = sp_OADestroy @zip
        EXEC @hr = sp_OADestroy @entry
        RETURN
      END

    -- ------------------------------------------------------------
    -- Inflate the ZIP entry directly into a BinData object.
    -- 
    -- The uncompressed bytes are stored entirely in memory.
    -- 
    DECLARE @pdfData int
    EXEC @hr = sp_OACreate 'Chilkat.BinData', @pdfData OUT

    EXEC sp_OAMethod @entry, 'UnzipToBd', @success OUT, @pdfData
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @entry, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @zip
        EXEC @hr = sp_OADestroy @entry
        EXEC @hr = sp_OADestroy @pdfData
        RETURN
      END


    EXEC sp_OAGetProperty @pdfData, 'NumBytes', @iTmp0 OUT
    PRINT 'Uncompressed size = ' + @iTmp0

    PRINT ''

    -- ------------------------------------------------------------
    -- Optionally save the uncompressed bytes to a file.
    -- 
    EXEC sp_OAMethod @pdfData, 'WriteFile', @success OUT, 'qa_output/report.pdf'
    IF @success = 0
      BEGIN
        EXEC sp_OAGetProperty @pdfData, 'LastErrorText', @sTmp0 OUT
        PRINT @sTmp0
        EXEC @hr = sp_OADestroy @zip
        EXEC @hr = sp_OADestroy @entry
        EXEC @hr = sp_OADestroy @pdfData
        RETURN
      END

    EXEC sp_OAMethod @zip, 'CloseZip', NULL


    PRINT 'PDF extracted successfully.'

    EXEC @hr = sp_OADestroy @zip
    EXEC @hr = sp_OADestroy @entry
    EXEC @hr = sp_OADestroy @pdfData


END
GO