PromptControl

Single-line text input with readline-style editing, history, selection, clipboard, and tab completion.

Overview

PromptControl provides a labeled text input field with rich editing capabilities including cursor navigation, word-level operations, text selection, clipboard support, command history, and tab completion. Supports password masking, horizontal scrolling, and mouse click-to-cursor.

Properties

Property	Type	Default	Description
`Prompt`	`string?`	`"> "`	Label text displayed before the input area (supports markup)
`Input`	`string`	`""`	Current input text
`MaskCharacter`	`char?`	`null`	Display character for password fields
`InputWidth`	`int?`	`null`	Input field width (auto-computed from available space if null)
`UnfocusOnEnter`	`bool`	`true`	Whether focus leaves the control on Enter
`HistoryEnabled`	`bool`	`false`	Enable Up/Down arrow command recall
`TabCompleter`	`Func<string, int, IEnumerable<string>?>?`	`null`	Tab completion delegate
`InputBackgroundColor`	`Color?`	Theme	Background when unfocused
`InputFocusedBackgroundColor`	`Color?`	Theme	Background when focused
`InputForegroundColor`	`Color?`	Theme	Foreground when unfocused
`InputFocusedForegroundColor`	`Color?`	Theme	Foreground when focused
`IsEnabled`	`bool`	`true`	Whether the control accepts input
`HasSelection`	`bool`	(read-only)	Whether text is currently selected
`SelectedText`	`string?`	(read-only)	The selected text, or null

Events

Event	Arguments	Description
`Entered`	`string`	Enter key pressed — provides the input text
`InputChanged`	`string`	Input text changed (typing, paste, delete)

Creating PromptControl

Using Builder (Recommended)

var prompt = Controls.Prompt("Search: ")
    .WithHistory()
    .WithMaskCharacter('*')  // password field
    .OnEntered((sender, text) => Console.WriteLine($"You entered: {text}"))
    .Build();

Using Constructor

var prompt = new PromptControl
{
    Prompt = "Enter name: ",
    UnfocusOnEnter = false,
    HistoryEnabled = true
};
prompt.Entered += (sender, text) => ProcessInput(text);

Keyboard Support

Key	Action
`Left Arrow`	Move cursor left
`Right Arrow`	Move cursor right
`Home` / `Ctrl+A`	Move to start (Ctrl+A selects all)
`End` / `Ctrl+E`	Move to end
`Ctrl+Left`	Move word left
`Ctrl+Right`	Move word right

Editing

Key	Action
`Backspace`	Delete character left (or delete selection)
`Delete`	Delete character right (or delete selection)
`Ctrl+K`	Kill from cursor to end of line
`Ctrl+U`	Kill from start to cursor
`Ctrl+W`	Kill word backward

Selection & Clipboard

Key	Action
`Shift+Left/Right`	Extend selection
`Shift+Home/End`	Extend selection to start/end
`Ctrl+A`	Select all
`Ctrl+C`	Copy selection to clipboard
`Ctrl+V`	Paste from clipboard
`Ctrl+X`	Cut selection to clipboard

History & Completion

Key	Action
`Up Arrow`	Previous history entry (when HistoryEnabled)
`Down Arrow`	Next history entry
`Tab`	Trigger tab completion (when TabCompleter is set)
`Enter`	Submit input (fires Entered, adds to history)
`Escape`	Clear focus

Mouse Support

Action	Result
Click	Focus control and position cursor at clicked character

Tab Completion

Set a TabCompleter delegate that returns completion candidates:

var prompt = Controls.Prompt("$ ")
    .WithTabCompleter((input, cursorPos) =>
    {
        var commands = new[] { "help", "exit", "clear", "history" };
        return commands.Where(c => c.StartsWith(input));
    })
    .WithHistory()
    .Build();

When Tab is pressed:

Single match: auto-completes the input
Multiple matches: inserts the longest common prefix
No matches: Tab passes through to focus traversal (no trap)

Examples

Password Input

var password = Controls.Prompt("Password: ")
    .WithMaskCharacter('●')
    .OnEntered((_, pwd) => Authenticate(pwd))
    .Build();

Command Line with History

var cli = Controls.Prompt("$ ")
    .WithHistory()
    .UnfocusOnEnter(false)
    .OnEntered((sender, cmd) =>
    {
        ExecuteCommand(cmd);
        ((PromptControl)sender!).SetInput("");
    })
    .Build();

URL Bar

var addressBar = Controls.Prompt($"{icon} ")
    .UnfocusOnEnter(false)
    .WithAlignment(HorizontalAlignment.Stretch)
    .OnEntered(async (sender, url) =>
    {
        await htmlControl.LoadUrlAsync(url);
    })
    .Build();

Best Practices

Use UnfocusOnEnter(false) for controls where the user types multiple inputs (command lines, search bars)
Use WithHistory() for command-line interfaces
Use WithMaskCharacter('●') for password fields
Tab completion returns false (passes through) when no matches — the user is never trapped
Ctrl+A selects all text; typing with a selection replaces it