Question

I have an autoupdater C# program. It will download a rar file that holds the changed or new files for the update to some software. The rar file has it’s structure just like the base directory of the software but only contains changed or new files/folders. Is there an easy way to “merge” these files/folders to the destination directory so in that if the file/folder exists already it’ll be replaced and if not it’ll be added or do I have to manually walk through each file/folder and do this myself? Just hoping there is a nice little merge function that .NET has 🙂

Answer 1

DirectoryInfo Class

The following example demonstrates how to copy a directory and its contents.

public static void CopyAll(DirectoryInfo source, DirectoryInfo target)
{
    if (source.FullName.ToLower() == target.FullName.ToLower())
    {
        return;
    }

    // Check if the target directory exists, if not, create it.
    if (Directory.Exists(target.FullName) == false)
    {
        Directory.CreateDirectory(target.FullName);
    }

    // Copy each file into it's new directory.
    foreach (FileInfo fi in source.GetFiles())
    {
        Console.WriteLine(@"Copying {0}\{1}", target.FullName, fi.Name);
        fi.CopyTo(Path.Combine(target.ToString(), fi.Name), true);
    }

    // Copy each subdirectory using recursion.
    foreach (DirectoryInfo diSourceSubDir in source.GetDirectories())
    {
        DirectoryInfo nextTargetSubDir =
            target.CreateSubdirectory(diSourceSubDir.Name);
        CopyAll(diSourceSubDir, nextTargetSubDir);
    }
}