从SQL Server获取zip文件列表

Question

I have a table in a SQL Server database with a varbinary(max) column with zip archives. How do I get a list of these archives without extracting them? My C# application reads the list of these archives, and I need to add more information about the content.

For file I use the ZipFile class from System.IO.Compression.FileSystem assembly, but how to pass varbinary data instead file name (if I create CLR Function, for example)?

Answer 1

Is this what you are looking for?

SQLCLR C# function...

using System.Data.SqlTypes;
using System.IO;
using System.IO.Compression;
using System.Linq;

public partial class UserDefinedFunctions
{
    [Microsoft.SqlServer.Server.SqlFunction]
    public static SqlString ZipEntries(SqlBytes data) {
        using (var stream = new MemoryStream(data.Value))
        using (var archive = new ZipArchive(stream))
            return new SqlString(string.Join(",", archive.Entries.Select(e => e.Name)));
    }
}

Here's the SQL I used to test. Surprisingly, it worked ...

-- Create table with ZIP archive column...
CREATE TABLE dbo.ZipImages(ZipArchive VARBINARY(MAX));
GO

-- ... then insert ZIP archive content into the dbo.ZipImages table ...
-- (code not included)
GO

-- ... then prove it works.
SELECT dbo.ZipEntries(ZipArchive) FROM dbo.ZipImages;
GO

It is possible/probable that your database will whine about System.IO.Compression not being available, in which case you can try ...

ALTER DATABASE [<your database>] SET TRUSTWORTHY ON;

CREATE ASSEMBLY [System.IO.Compression]
FROM N'C:\Windows\Microsoft.NET\Framework\v4.0.30319\System.IO.Compression.dll'
WITH PERMISSION_SET = EXTERNAL_ACCESS;

(If you're not the DBA, you'll want to make friends quickly.)

This is just a bare-bones UDF, obviously -- you probably want to do something a bit different (like make it a table-based CLR UDF to return the entries one-by-one).

If you need to open files from the archive in the data column, it gets trickier. Among other things, you will have to add System.IO.Compression.File as an assembly, which is (unfortunately) UNSAFE and complicates a bunch of things...

CREATE ASSEMBLY [System.IO.Compression.FileSystem]
FROM N'C:\Windows\Microsoft.NET\Framework\v4.0.30319\System.IO.Compression.FileSystem.dll'
WITH PERMISSION_SET = UNSAFE;