PromptPlus

# PromptPlus ## **Slider — Methods** [![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: Slider — Operations →

Every fluent method on ISliderControl. Each returns the same control instance, so calls chain in any order. Call Run last.

The factory is PromptPlus.Controls.Slider(string prompt = "", string? description = null), which returns ISliderControl.

Quick jump: Range · Width · FractionalDigits · Culture · Default · Step · LargeStep · BarType · Layout · ChangeColor · ChangeGradient · HideElements · EnableHistory · ChangeDescription · ChangeDescriptionAsync · Styles · Options · Run

Range & precision

`Range`

ISliderControl Range(double minvalue, double maxvalue)

Defines the lower and upper limits the slider can reach. Defaults to 0 and 100.

Parameter	Meaning
`minvalue`	The smallest value the user can select.
`maxvalue`	The largest value the user can select.

PromptPlus.Controls.Slider("Score")
    .Range(0, 10)
    .Run();

Throws ArgumentOutOfRangeException when minvalue is greater than or equal to maxvalue.

`Width`

ISliderControl Width(byte value)

Sets the width of the bar, measured in console characters. Default is 30; the value must be between 10 and 100.

PromptPlus.Controls.Slider("Value", "Bar drawn with 60 characters")
    .Width(60)
    .Run();

Throws ArgumentOutOfRangeException when value is less than 10 or greater than 100. An odd width is silently rounded up by one to the next even number — there’s no warning, the bar is just one character wider than requested.

`FractionalDigits`

ISliderControl FractionalDigits(byte value)

Sets how many decimal places are shown for the value. Default is 0 (whole numbers); the maximum is 5.

PromptPlus.Controls.Slider("Ratio")
    .Range(0, 1)
    .FractionalDigits(2)
    .Run();

Throws ArgumentOutOfRangeException when value is greater than 5.

`Culture`

Two overloads control how the number is formatted (decimal separator, digit grouping). Both default to the current PromptPlus culture.

ISliderControl Culture(CultureInfo culture)
ISliderControl Culture(string cultureName)

Overload	Meaning
`Culture(CultureInfo)`	Pass a `CultureInfo` directly. Cannot be `null`.
`Culture(string)`	Pass a culture name such as `"en-US"` or `"pt-BR"`.

PromptPlus.Controls.Slider("Preço", "Value formatted with pt-BR culture")
    .Culture("pt-BR")            // comma decimal separator
    .Range(0, 10)
    .FractionalDigits(2)
    .Step(0.25)
    .Run();

The string overload throws ArgumentNullException for a null name, resolves an empty string to the invariant culture (no throw), and throws CultureNotFoundException for an unrecognized name.

Starting value

`Default`

ISliderControl Default(double value, bool useDefaultHistory = true)

Sets the value that is pre-selected when the slider is first shown. If never called, the slider starts at Range’s minimum, not a literal 0 — for a range that doesn’t include 0 (e.g. Range(10, 50)), the true default is 10.

Parameter	Meaning
`value`	The initial value. Must be inside the range from `Range`.
`useDefaultHistory`	When `true` and history is enabled via `EnableHistory`, the last saved value is used instead of `value`. Default `true`.

PromptPlus.Controls.Slider("Value")
    .Range(-50, 50)
    .Default(0)
    .Run();

Default itself does no range check — it just stores value. The out-of-range check happens when the control runs: if the (possibly history-overridden) starting value ends up outside Range, Run() throws InvalidOperationException, not ArgumentOutOfRangeException.

Step increments

`Step`

ISliderControl Step(double value)

Sets the amount added or removed on each small change (the arrow keys). Default is 1/100 of the range (so 1 for the default 0..100 range).

PromptPlus.Controls.Slider("Value")
    .Step(0.5)
    .Run();

`LargeStep`

ISliderControl LargeStep(double value)

Sets the amount added or removed on each large change (Tab / Shift+Tab). Default is 1/10 of the range (so 10 for the default 0..100 range).

PromptPlus.Controls.Slider("Value")
    .Step(0.5)
    .LargeStep(5)
    .Run();

Bar appearance & layout

`BarType`

ISliderControl BarType(SliderBarType type)

Selects the character set used to draw the bar. Default is SliderBarType.Fill.

`SliderBarType`	Bar drawn with
`Fill`	Solid fill blocks (default)
`Light`	Light line characters
`DoubleLight`	Double light line characters
`Square`	Square characters
`Dot`	Dotted characters

PromptPlus.Controls.Slider("Value", "Bar style: Square")
    .BarType(SliderBarType.Square)
    .Run();

`Layout`

ISliderControl Layout(SliderLayout value)

Chooses how the user changes the value and how the control is drawn. Default is SliderLayout.LeftRight.

`SliderLayout`	Behavior
`LeftRight`	Left / Right arrows change the value and the horizontal bar (with its delimiters) is shown (default)
`UpDown`	Up / Down arrows change the value; the bar and its delimiters are hidden, but the `[min,max]` range display is still shown next to the answer unless you also hide it with `HideElements(HideSlider.Range)`

PromptPlus.Controls.Slider("Value")
    .Layout(SliderLayout.UpDown)
    .Run();

`ChangeColor`

ISliderControl ChangeColor(Func<double, Style> value)

Colors the bar dynamically according to the current value — for example red when low and gold when high. The callback receives the current value and returns the Style to apply.

using PromptPlusLibrary;
using ConsolePlusLibrary;   // Color, Style live here

PromptPlus.Controls.Slider("Value", "Red <= 30, Blue <= 70, Gold > 70")
    .ChangeColor(value =>
    {
        if (value <= 30) return new Style(Color.Red, Color.Red);
        if (value <= 70) return new Style(Color.Blue, Color.Blue);
        return new Style(Color.Darkgoldenrod, Color.Darkgoldenrod);
    })
    .Run();

Throws ArgumentNullException if value is null.

`ChangeGradient`

ISliderControl ChangeGradient(params Color[] colors)

Paints the bar with a gradient that transitions across the supplied colors as the value grows.

using PromptPlusLibrary;
using ConsolePlusLibrary;

PromptPlus.Controls.Slider("Value")
    .ChangeGradient(Color.Green, Color.Yellow, Color.Red)
    .Run();

Throws ArgumentNullException if colors is null or empty — but a single color is legal (a solid, non-gradient bar); “two or more” is not a requirement. Use ChangeColor for threshold logic and ChangeGradient for a smooth blend — pick one approach per control.

`HideElements`

ISliderControl HideElements(HideSlider value)

Hides one or more decorative elements. By default every element is shown. HideSlider is a [Flags] enum — combine values with a bitwise OR.

`HideSlider`	Effect
`None`	Nothing hidden (default)
`Delimit`	Hides the delimiters
`Range`	Hides the min/max range display

PromptPlus.Controls.Slider("Value")
    .HideElements(HideSlider.Delimit | HideSlider.Range)
    .Run();

History

`EnableHistory`

ISliderControl EnableHistory(string filename, Action<IHistoryOptions>? options = null)

Persists the confirmed value to a file under filename so it can be reused as the default on the next run.

Parameter	Meaning
`filename`	A stable, unique key for this slider’s history store. Cannot be `null`, empty, or whitespace.
`options`	Optional `IHistoryOptions` configuration (expiration, max items, and so on).

PromptPlus.Controls.Slider("Value")
    .Default(0, true)                 // fall back to the last history value
    .FractionalDigits(2)
    .Step(0.5)
    .LargeStep(5)
    .EnableHistory("slider-history")
    .Run();

Throws ArgumentException if filename is empty or whitespace (ArgumentNullException if null).

💡 Pair Default(value, useDefaultHistory: true) with EnableHistory(...) to pre-load the last value the user confirmed. See Operations → History for runtime behavior.

Dynamic description

`ChangeDescription`

ISliderControl ChangeDescription(Func<double, string> value)

Recomputes the description line as the value changes. The callback receives the current value and returns the description to display — handy for live readouts.

PromptPlus.Controls.Slider("Value")
    .ChangeDescription(value => $"Current selection: {value:0} %")
    .Run();

Throws ArgumentNullException if value is null.

`ChangeDescriptionAsync`

ISliderControl ChangeDescriptionAsync(Func<double, Task<string>> value)

Asynchronous version of ChangeDescription, for a description sourced asynchronously.

PromptPlus.Controls.Slider("Value")
    .ChangeDescriptionAsync(async value =>
    {
        await Task.Delay(1).ConfigureAwait(false);
        return $"Async description for value {value:0}";
    })
    .Run();

Throws ArgumentNullException if value is null.

Appearance & behavior

`Styles`

ISliderControl Styles(SliderStyles styleType, Style style)

Overrides the color of one visual region of this control instance. See the full region list and examples on the Styles page.

using PromptPlusLibrary;
using ConsolePlusLibrary;

PromptPlus.Controls.Slider("Value")
    .Styles(SliderStyles.Prompt, new Style(Color.Aqua, Color.Black))
    .Styles(SliderStyles.Answer, new Style(Color.Green, Color.Black))
    .Styles(SliderStyles.Slider, new Style(Color.Blue, Color.Black))
    .Run();

Throws ArgumentNullException if style is null.

`Options`

ISliderControl Options(Action<IControlOptions> options)

Overrides global behaviors (PromptPlus.Config) for this one control — prompt/description text, abort key, tooltip, hide-after-finish, and the extra-info affixes.

PromptPlus.Controls.Slider("Value")
    .Options(opt =>
    {
        opt.Description("Custom options sample");
        opt.ShowTooltip(false);
        opt.EnabledAbortKey(true);
        opt.HideAfterFinish(false);
    })
    .Run();

See Global Behaviors → Per-Control Override for the complete IControlOptions list.

Throws ArgumentNullException if options is null.

Running the control

`Run`

ResultPrompt<double?> Run(CancellationToken token = default)

Renders the slider and blocks until the user confirms (Enter) or aborts (Esc). Returns a ResultPrompt<double?> whose .Content is null when the prompt is cancelled.

Parameter	Meaning
`token`	A `CancellationToken` that cancels the prompt while it waits for input.

using var cts = new CancellationTokenSource(TimeSpan.FromSeconds(5));
var result = PromptPlus.Controls.Slider("Value").Run(cts.Token);

PromptPlus

Range & precision

Range

Width

FractionalDigits

Culture

Starting value

Default

Step increments

Step

LargeStep

Bar appearance & layout

BarType

Layout

ChangeColor

ChangeGradient

HideElements

History

EnableHistory

Dynamic description

ChangeDescription

ChangeDescriptionAsync

Appearance & behavior

Styles

Options

Running the control

Run

See also

`Range`

`Width`

`FractionalDigits`

`Culture`

`Default`

`Step`

`LargeStep`

`BarType`

`Layout`

`ChangeColor`

`ChangeGradient`

`HideElements`

`EnableHistory`

`ChangeDescription`

`ChangeDescriptionAsync`

`Styles`

`Options`

`Run`