copy file inside a zip into a new zip

[MichaelJohnBradley]

Hi

Could someone help explain how i can do the following.

In an existing zip file (that i have as a file stream) i need to loop through each file inside the zip/zip entry and maybe copy the file into a new zip file.

Is is possible to do this without decompressing each file?

[piksel]

I think it should be possible like this:

using System.IO;
using System.Collections.Generic;
using ICSharpCode.SharpZipLib.Zip;
	
var tempFiles = new List<string>();

using var zf = new ZipFile("outputfile.zip");
using (var zis = new ZipInputStream(File.OpenRead("inputfile.zip"))) {
	while (zis.GetNextEntry() is ZipEntry entry) {
        // Let's say we only want to copy PDF files
		if (entry.Name.EndsWith(".pdf")) {
            // Extract the file we want to a temporary file
			var tempFile = Path.GetTempFileName();
			using (var fs = File.Create(tempFile)) {
				zis.CopyTo(fs);
			}
            tempFiles.Add(tempFile);
            // Add the new entry to the pending updates (does not perform the changes yet)
			zf.Add(tempFile, entry.Name);
		}
	}
}

if (tempFiles.Count > 0) {
	// Write the new entries to the output zip file
	zf.CommitUpdate();
	// Cleanup temp files
	tempFiles.ForEach(f => File.Delete(f));
}

You could avoid extracting the files you want to transfer as well, but it's a bit more complicated.

[MichaelJohnBradley]

Thanks for that. Would you know how to do the more complicated way to avoid extracting the file each time?

…

________________________________ From: nils måsén ***@***.***> Sent: 25 May 2023 16:46 To: icsharpcode/SharpZipLib ***@***.***> Cc: Michael Bradley ***@***.***>; Author ***@***.***> Subject: Re: [icsharpcode/SharpZipLib] copy file inside a zip into a new zip (Discussion #835) I think it should be possible like this: using System.IO; using System.Collections.Generic; using ICSharpCode.SharpZipLib.Zip; var tempFiles = new List<string>(); using var zf = new ZipFile("outputfile.zip"); using (var zis = new ZipInputStream(File.OpenRead("inputfile.zip"))) { while (zis.GetNextEntry() is ZipEntry entry) { // Let's say we only want to copy PDF files if (entry.Name.EndsWith(".pdf")) { // Extract the file we want to a temporary file var tempFile = Path.GetTempFileName(); using (var fs = File.Create(tempFile)) { zis.CopyTo(fs); } tempFiles.Add(tempFile); // Add the new entry to the pending updates (does not perform the changes yet) zf.Add(tempFile, entry.Name); } } } if (tempFiles.Count > 0) { // Write the new entries to the output zip file zf.CommitUpdate(); // Cleanup temp files tempFiles.ForEach(f => File.Delete(f)); } You could avoid extracting the files you want to transfer as well, but it's a bit more complicated. — Reply to this email directly, view it on GitHub<#835 (comment)>, or unsubscribe<https://github.com/notifications/unsubscribe-auth/AGZXAY33QDS7XQTZOYNIGMLXH55FTANCNFSM6AAAAAAYOU65MI>. You are receiving this because you authored the thread.Message ID: ***@***.***>