Test-ConsoleWindowWithoutBufferCleaning

Test-ConsoleWindowWithoutBufferCleaning.ps1

# test script for interactive console window.
# currently cannot prevent mouse scrolling.
function Test-ConsoleWindowWithoutBufferCleaning {
    # backup cursor x position.
    $x = [Console]::CursorLeft

    # add lines to the end of the screen for scrolling using the PSReadLine method.
    # https://github.com/PowerShell/PSReadLine/blob/e57f7d691d8df8c1121fddf47084f96aea74a688/PSReadLine/DisplayBlockBase.cs#L17-L24
    $h = [Console]::WindowHeight
    0..($h - 1) | ForEach-Object { [Console]::Write("`n") }

    # write contents.
    $yy = [COnsole]::CursorTop
    $yy .. 0 | ForEach-Object {
        [Console]::SetCursorPosition($x, $_)
        [Console]::Write("Line: $_")
    }

    # some interaction.
    $arr = @()
    while ($true) {
        $k = [Console]::ReadKey()
        $arr = @($k) + $arr
        if ($k.Key -eq 'Enter') {
            break
        }
        else {
            $i = 0
            (($arr | Out-String ) -split "`n" ) | Select-Object -First $h | ForEach-Object {
                [Console]::SetCursorPosition(0, $i)
                [Console]::Write($_)
                $i += 1
            }
        }
    }

    # clear contests.
    $w = [Console]::WindowWidth
    0..($h - 1) | ForEach-Object {
        [Console]::SetCursorPosition(0, $_)
        [Console]::Write(' ' * $w)
    }

    # restore cursor position.
    [Console]::SetCursorPosition($x, 0)
}

Test-ConsoleWindowWithoutBufferCleaning

testConsoleWindowWithoutBufferCleaning.fsx

open System

[<TailCall>]
let rec readAndDisplay h w arr =
    let k = Console.ReadKey(true)
    let arr = k :: arr

    if k.Key = ConsoleKey.Enter then
        ()
    else
        let take =
            match List.length arr < h with
            | true -> List.length arr
            | _ -> h

        arr
        |> List.take take
        |> List.map (fun k -> $"[{k.Key} - {k.Modifiers}]")
        |> List.iteri (fun i s ->
            Console.SetCursorPosition(0, i)
            let s = $"{i} {s}"

            Console.Write(s + String.replicate (w - String.length s) " "))

        readAndDisplay h w arr

// test script for interactive console window.
// currently cannot prevent mouse scrolling.
let testConsoleWindowWithoutBufferCleaning () =
    // backup cursor x position.
    let x = Console.CursorLeft

    // add lines to the end of the screen for scrolling using the PSReadLine method.
    let h = Console.WindowHeight
    let w = Console.WindowWidth

    String.replicate (h - 1) "\n" |> Console.Write

    // write contents.
    let yy = Console.CursorTop

    Console.SetCursorPosition(0, 0)

    [ 0..yy ]
    |> List.map (fun i ->
        let s = $"Line: %d{i}"
        s + String.replicate (w - s.Length) " ")
    |> String.concat "\n"
    |> Console.Write
    // read and display.
    readAndDisplay h w []

    // clear contests.
    [ 0 .. (h - 1) ]
    |> List.iter (fun i ->
        Console.SetCursorPosition(0, i)
        Console.Write(String.replicate w " "))

    // restore cursor position.
    Console.SetCursorPosition(x, 0)

testConsoleWindowWithoutBufferCleaning ()