Working with Directories

Overview

Directory operations live on IAbsoluteDirectoryPath. Like files, relative directory paths can describe a location but cannot perform I/O; combine them with an absolute base directory first.

This article covers existence, creation, deletion and the small set of directory-specific properties. Enumeration and searching live in their own article. See Searching and Enumeration.

Existence Checks

Same model as files: Exists for a quick boolean, State for a richer answer:

if (!dir.Exists)
    dir.Create();

switch (dir.State)
{
    case EntryState.Exists:             /* good to go */ break;
    case EntryState.ParentExists:       /* parent is there, can create */ break;
    case EntryState.ParentDoesNotExist: /* Create() will still work */ break;
    case EntryState.WrongType:          /* a file is here */ break;
}

See the table in Working with Files for the full meaning of each EntryState value.

Creating Directories

Create creates the directory and any missing parent directories. It is idempotent; calling it on an already-existing directory does nothing.

IAbsoluteDirectoryPath logsDir = appBase.CombineDirectory("logs/2026/04");
logsDir.Create();   // creates logs, 2026 and 04 as needed
Tip

Before writing a file at a new location, the simplest pattern is file.ParentDirectory.Create(), a single call that ensures every directory in the chain exists.

Deleting Directories

Delete has the following signature:

void Delete(bool recursive = false, bool ignoreNotFound = true);

Default behavior:

  • Non-recursive (the directory must be empty, otherwise IOException is thrown).
  • Missing directories are ignored silently.
dir.Delete();                             // empty directories only
dir.Delete(recursive: true);              // remove children too
dir.Delete(ignoreNotFound: false);        // throw if absent
dir.Delete(recursive: true, ignoreNotFound: false);
Caution

recursive: true is destructive: every file and subdirectory below the path is removed. Confirm the path is what you expect before calling it on user-influenced input.

Moving Directories

Use MoveTo to rename or relocate a directory:

dir.MoveTo(targetDir);

The argument is the new path of the directory itself, not its parent. The destination must be on the same volume and must not already exist; otherwise IOException is thrown. To move across volumes, enumerate the contents and copy them instead (see the Mirror a structure pattern below).

Useful Properties

IsRoot

IsRoot is true for a root directory (C:\, /, a UNC share root). Roots have no parent; HasParentDirectory is false.

file.RootDirectory.IsRoot;   // true

IsEmpty

IsEmpty returns true if the directory exists and contains no entries:

if (dir.Exists && dir.IsEmpty)
    dir.Delete();

IsEmpty requires the directory to exist; otherwise the underlying API throws.

Attributes and Timestamps

Inherited from IAbsolutePath. Same surface as files:

dir.Attributes;
dir.CreationTimeUtc;
dir.LastWriteTimeUtc = DateTime.UtcNow;

For a single consistent snapshot, call GetInfo to obtain a CachedDirectoryInfo. See Cached Entry Info.

Common Patterns

Clear a directory

dir.Delete(recursive: true);
dir.Create();

This is the simplest reliable way to start from an empty directory. It avoids enumerate-and-delete races.

Mirror a structure

foreach (IRelativeFilePath rel in source.GetRelativeChildFiles("*", new SearchOptions { Recursive = true }))
{
    IAbsoluteFilePath dest = target + rel;
    dest.ParentDirectory.Create();
    (source + rel).CopyTo(dest, overwrite: true);
}

See Searching and Enumeration for the full enumeration surface.

Preserve only certain content

foreach (IAbsoluteFilePath log in dir.GetChildFiles("*.log"))
{
    if (log.LastWriteTimeUtc < DateTime.UtcNow.AddDays(-7))
        log.Delete();
}

Disk Space and Drive Type

Every absolute directory exposes disk-space information for the volume it lives on via AvailableFreeSpace, TotalFreeSpace, TotalSize, DriveType and FileSystem:

dir.AvailableFreeSpace;
dir.TotalFreeSpace;
dir.TotalSize;
dir.DriveType;
dir.FileSystem;   // e.g. "NTFS"

See Drive and Disk Information.

Next Steps