IOException file already exists C#

Question

private void btn_Backup_Click(object sender, EventArgs e)
    {
        List<DirectoryInfo> SourceDir = this.lbox_Sources.Items.Cast<DirectoryInfo>().ToList();
        string TargetDir = this.tbox_Target.Text;

        foreach (DirectoryInfo directory in SourceDir)
        {
            foreach (var file in directory.GetFiles())
                if (this.checkbox_zipfiles.Checked == true)
                {
                    System.IO.Compression.ZipFile.CreateFromDirectory(directory.FullName, TargetDir + @"\test.zip");
                }
                else
                {
                    Microsoft.VisualBasic.FileIO.FileSystem.CopyDirectory(directory.FullName, TargetDir, true);
                }
        }
    }

I'm creating a backup application and when I try to zip the files I need to backup it says: "The file 'C:\\Users\\Lada1208\\Desktop\\test\\test.zip' already exists." even thought the folder is empty before so it's trying to create the test.zip file two times for some reason. Any idea why?

Answer 1

As pointed out by sm in the comment above, the call to ZipFile.CreateFromDirectory() will attempt to create a zip file with the same location and file name for all the source directories.

If the intention is to create a single archive containing files from all the source directories, then the Zipfile.CreateFromDirectory() "shortcut" method cannot be used. Instead, you need to call ZipFile.Open(), get a ZipArchive object and use its CreateEntry() method to add every file individually.