PromptPlus

# PromptPlus ## **File — Operations** [![NuGet](https://img.shields.io/badge/NuGet-PromptPlus-blue)](https://www.nuget.org/packages/PromptPlus) [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](https://opensource.org/licenses/MIT) [![.NET](https://img.shields.io/badge/.NET-8%20%7C%209%20%7C%2010-512BD4)](https://dotnet.microsoft.com/)

← Back to Home • Next: File — Styles →

How the File control behaves while it is running: keyboard, tree navigation, filtering, selection rules, history, and the values it returns.

Anatomy of the control

Select a file or folder: index.md  1.2 KB ← prompt + live answer (path + size, follows the cursor)
Press + to expand, - to collapse         ← description (optional) — NOT ←/→, see Tree navigation
C:\Projects                              ← root folder
├─ ▶ src                                 ← collapsed folder (expand symbol)
├─ ▼ docs                                ← expanded folder
│    › index.md          1.2 KB          ← focused item + size column
│      styles.md         3.4 KB
└─ README.md             0.8 KB
Page 1/2                                 ← pagination
Enter: select  Esc: cancel               ← tooltip

The answer line shows the size next to the path for a focused file (omitted for folders, and omitted entirely when HideSize is set) — the same information as the list row, but reachable via Home/End/←/→ scrolling if the path is too long to fit.

Every region can be recolored — see Styles.

File is a lazy tree browser: a folder’s children are read only when you expand it, and released when you collapse it. This keeps memory proportional to what is visible, so it is safe to point Root at a large drive.

Key	Action
`↑` / `↓`	Move focus up / down
`+`	Expand the focused folder (plain `→` does not expand)
`-`	Collapse the focused folder (plain `←` does not collapse)
`Tab`	On a folder: expand it (if needed) and move to its first child. On a file: move to the next item
`Shift+Tab`	On a folder’s first child: collapse the parent and move to it. Otherwise: move to the previous item
`Page Up` / `Page Down`	Jump one page
`Ctrl+Home` / `Ctrl+End`	First / last visible item (plain `Home`/`End` instead scroll the long-path answer text — see the anatomy note above)
Any printable character	Jump to the next visible entry whose name starts with that character (wraps around)
`Enter`	Confirm the focused entry (subject to the selection rule)
`Esc`	Abort → `IsAborted == true`
`Shift+F3`	Toggle the answer between full path and short name
`F1`	Cycle tooltip content
`Ctrl+F1`	Show / hide the tooltip

What is listed

SearchPattern filters files by wildcard (e.g. *.cs); directories are always shown so you can navigate into them.
OnlyFolders hides files entirely — a folder picker.
ShowHidden and ShowSystem add entries that carry the Hidden/System attribute; both are off by default. ShowSystem has no effect at all on non-Windows platforms (the System attribute isn’t checked there); ShowHidden on Unix uses a separate check based on a leading dot in the file name, since Unix has no Hidden file attribute.
HideSize removes the size column shown next to files.

Selection rules

Pressing Enter confirms the focused entry and closes the control — but what counts as a valid selection depends on the configuration:

By default, either a file or a folder can be confirmed.
With SelectFilesOnly, folders can be expanded and browsed, but only a file can be confirmed.
With OnlyFolders, files are not listed at all, so only folders are available.

The confirmed entry is returned as a FileItem.

Full-path display

The answer line (and, when enabled, the summary) shows either the entry’s short name or its full path. ShowFullPath sets the initial choice; the user can flip it at any time with Shift+F3. This affects only the display — .Content.FullPath always carries the complete path.

Initial selection & history

Default(fullPath) pre-selects an entry and expands the tree down to it when the path lies under the Root.
With EnableHistory, the confirmed path is stored on disk; on the next run it becomes the default and the tree expands to it (unless overridden by an explicit Default with useDefaultHistory: false).
History options (MinPrefixLength, MaxItems, ExpirationTime, FilterType, PageSize) match the Input history options.

The `FileItem` result

Run() returns ResultPrompt<FileItem?>. FileItem is a sealed class (not System.IO.FileInfo — there is no FullName):

Member	Type	Meaning
`FullPath`	`string`	Full path on disk (`ToString()` returns this)
`Name`	`string`	Display name of the entry
`IsDirectory`	`bool`	`true` for folders
`Length`	`long`	Size in bytes; `0` for directories
`LastWriteTime`	`DateTime`	Last write timestamp

var result = PromptPlus.Controls.File("Pick").Root(root).Run();
if (!result.IsAborted && result.Content is not null)
{
    var f = result.Content;
    PromptPlus.Console.WriteLine($"{f.FullPath} (dir: {f.IsDirectory}, size: {f.Length})");
}

Options that change behavior

Set per instance via Options(...), or globally on PromptPlus.Config:

Option	Effect on `File`
`EnabledAbortKey(false)`	Removes Esc — the user must choose
`HideAfterFinish(true)`	Erases the tree after confirm — the whole control is erased, not just the interactive part
`ShowTooltip(false)`	Hides the keyboard hint line
`Prompt(...)` / `Description(...)`	Overrides the prompt / description text

PageSize can be set per control (PageSize) or globally (PromptPlus.Config.PageSize).

Edge cases & gotchas

Aborted results carry .Content == null. Always branch on IsAborted before dereferencing.
FileItem is not FileInfo — use FullPath, not FullName.
Length is 0 for directories — check IsDirectory before treating it as a file size.
SearchPattern filters files only — folders always appear so the tree remains navigable.
Large roots are fine — lazy loading means only expanded folders are read.