PromptPlus

# PromptPlus ## **File** [![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 — Methods →

A lazy-loaded file-system tree where the user browses folders and picks one file or folder, confirming with Enter.

File renders the file system as an expandable/collapsible tree rooted at a folder you choose. It loads each directory’s contents only when the folder is expanded (and releases them when collapsed), so memory stays proportional to what is on screen — not to the size of the drive. You can filter files by pattern, list folders only, restrict selection to files, show or hide hidden/system entries, and pre-select a path.

☑️ Need to pick several files or folders at once? Use the MultiFile control — same tree browser, with checkboxes.

Sub-page	What you will find
Index (this page)	What it is, when to use it, first examples, the method map
Methods	Every fluent method — signature, parameters, defaults, and a snippet
Operations	Keyboard, tree navigation, filtering, selection rules, history
Styles	The `FileStyles` regions and how to recolor them

When to use it

Use `File` when…	Consider instead…
The user picks one file or folder from disk	—
The user may pick several files/folders	MultiFile
The data is an arbitrary hierarchy (not the file system)	TreeSelect
The choice is from an in-memory list	Select
The data is tabular (multiple columns)	TableSelect

Minimal example

using PromptPlusLibrary;

var result = PromptPlus.Controls
    .File("Select a file or folder")
    .Root(@"C:\Projects")
    .Run();

if (!result.IsAborted)
    PromptPlus.Console.WriteLine($"You chose {result.Content?.FullPath}");

File("Select a file or folder") creates the browser; the argument is the prompt text.
.Root(...) sets the folder the tree starts at. Without it, the current directory is used.
.Run() renders the tree and blocks until Enter (confirm) or Esc (abort), returning a ResultPrompt<FileItem?>.

Reading the result

Run() returns ResultPrompt<FileItem?>. FileItem is a small sealed class — not System.IO.FileInfo — describing the chosen entry:

var result = PromptPlus.Controls.File("Pick a file").Root(root).Run();

if (!result.IsAborted && result.Content is not null)
{
    var f = result.Content;
    PromptPlus.Console.WriteLine(f.FullPath);        // full path on disk
    PromptPlus.Console.WriteLine(f.Name);            // display name
    PromptPlus.Console.WriteLine($"{f.IsDirectory}"); // folder or file?
    PromptPlus.Console.WriteLine($"{f.Length} bytes");// 0 for directories
    PromptPlus.Console.WriteLine($"{f.LastWriteTime}");
}

FileItem.ToString() returns FullPath, so the item prints as its path.

A richer example

using PromptPlusLibrary;

var result = PromptPlus.Controls
    .File("Select a C# file", "Right/+ expand, Left/- collapse, Enter to select")
    .Root(@"C:\Projects")
    .SearchPattern("*.cs")   // only *.cs files are listed (folders always show)
    .SelectFilesOnly()       // folders can be expanded but not returned
    .HideSize()              // drop the size column
    .PageSize(12)            // 12 visible rows
    .Run();

This combines a file filter, a selection rule, and paging — see Operations for how they behave together.

Method map

Grouped by purpose. Full signatures and examples are on the Methods page.

Purpose	Methods
Choose the root	`Root`
Filter what is listed	`SearchPattern`, `OnlyFolders`, `ShowHidden`, `ShowSystem`
Selection rule	`SelectFilesOnly`
Layout & display	`HideSize`, `ShowFullPath`, `PageSize`
Initial value	`Default`
History	`EnableHistory`
Appearance & behavior	`Styles`, `Options`
Run	`Run`

Return value

File returns ResultPrompt<FileItem?> — the single chosen entry.

Member	Meaning
`.Content`	The selected `FileItem` (`null` if aborted)
`.IsAborted`	`true` when the user pressed Esc

var (item, aborted) = PromptPlus.Controls.File("Pick").Root(root).Run();
if (!aborted) PromptPlus.Console.WriteLine(item?.FullPath);