Console.Clear Method (System) (2023)

public: static void Clear();

public static void Clear ();

[System.Runtime.Versioning.UnsupportedOSPlatform("android")][System.Runtime.Versioning.UnsupportedOSPlatform("ios")][System.Runtime.Versioning.UnsupportedOSPlatform("tvos")]public static void Clear ();

static member Clear : unit -> unit

[<System.Runtime.Versioning.UnsupportedOSPlatform("android")>][<System.Runtime.Versioning.UnsupportedOSPlatform("ios")>][<System.Runtime.Versioning.UnsupportedOSPlatform("tvos")>]static member Clear : unit -> unit

Public Shared Sub Clear ()

Attributes

UnsupportedOSPlatformAttribute

Exceptions

Examples

The following example uses the Clear method to clear the console before it executes a loop, prompts the user to select a foreground and background color and to enter a string to display. If the user chooses not to exit the program, the console's original foreground and background colors are restored and the Clear method is called again before re-executing the loop.

using System;public class Example{ public static void Main() { // Save colors so they can be restored when use finishes input. ConsoleColor dftForeColor = Console.ForegroundColor; ConsoleColor dftBackColor = Console.BackgroundColor; bool continueFlag = true; Console.Clear(); do { ConsoleColor newForeColor = ConsoleColor.White; ConsoleColor newBackColor = ConsoleColor.Black; Char foreColorSelection = GetKeyPress("Select Text Color (B for Blue, R for Red, Y for Yellow): ", new Char[] { 'B', 'R', 'Y' } ); switch (foreColorSelection) { case 'B': case 'b': newForeColor = ConsoleColor.DarkBlue; break; case 'R': case 'r': newForeColor = ConsoleColor.DarkRed; break; case 'Y': case 'y': newForeColor = ConsoleColor.DarkYellow; break; } Char backColorSelection = GetKeyPress("Select Background Color (W for White, G for Green, M for Magenta): ", new Char[] { 'W', 'G', 'M' }); switch (backColorSelection) { case 'W': case 'w': newBackColor = ConsoleColor.White; break; case 'G': case 'g': newBackColor = ConsoleColor.Green; break; case 'M': case 'm': newBackColor = ConsoleColor.Magenta; break; } Console.WriteLine(); Console.Write("Enter a message to display: "); String textToDisplay = Console.ReadLine(); Console.WriteLine(); Console.ForegroundColor = newForeColor; Console.BackgroundColor = newBackColor; Console.WriteLine(textToDisplay); Console.WriteLine(); if (Char.ToUpper(GetKeyPress("Display another message (Y/N): ", new Char[] { 'Y', 'N' } )) == 'N') continueFlag = false; // Restore the default settings and clear the screen. Console.ForegroundColor = dftForeColor; Console.BackgroundColor = dftBackColor; Console.Clear(); } while (continueFlag); } private static Char GetKeyPress(String msg, Char[] validChars) { ConsoleKeyInfo keyPressed; bool valid = false; Console.WriteLine(); do { Console.Write(msg); keyPressed = Console.ReadKey(); Console.WriteLine(); if (Array.Exists(validChars, ch => ch.Equals(Char.ToUpper(keyPressed.KeyChar)))) valid = true; } while (! valid); return keyPressed.KeyChar; }}

open Systemlet getKeyPress msg validChars = Console.WriteLine() let mutable valid = false let mutable keyChar = ' ' while not valid do printfn "%s" msg let keyPressed = Console.ReadKey() printfn "" if validChars |> List.exists (fun ch -> ch.Equals(Char.ToUpper keyPressed.KeyChar)) then valid <- true keyChar <- keyPressed.KeyChar keyChar// Save colors so they can be restored when use finishes input.let dftForeColor = Console.ForegroundColorlet dftBackColor = Console.BackgroundColorlet mutable continueFlag = trueConsole.Clear()while continueFlag do let foreColorSelection = getKeyPress "Select Text Color (B for Blue, R for Red, Y for Yellow): " [ 'B'; 'R'; 'Y' ] let newForeColor = match foreColorSelection with | 'B' | 'b' -> ConsoleColor.DarkBlue | 'R' | 'r' -> ConsoleColor.DarkRed | 'Y' | 'y' -> ConsoleColor.DarkYellow | _ -> ConsoleColor.White let backColorSelection = getKeyPress "Select Background Color (W for White, G for Green, M for Magenta): " [ 'W'; 'G'; 'M' ] let newBackColor = match backColorSelection with | 'W' | 'w' -> ConsoleColor.White | 'G' | 'g' -> ConsoleColor.Green | 'M' | 'm' -> ConsoleColor.Magenta | _ -> ConsoleColor.Black printfn "" printf "Enter a message to display: " let textToDisplay = Console.ReadLine() printfn "" Console.ForegroundColor <- newForeColor Console.BackgroundColor <- newBackColor printfn "%s" textToDisplay printfn "" if Char.ToUpper(getKeyPress "Display another message (Y/N): " [ 'Y'; 'N' ] ) = 'N' then continueFlag <- false // Restore the default settings and clear the screen. Console.ForegroundColor <- dftForeColor Console.BackgroundColor <- dftBackColor Console.Clear()

Module Example Public Sub Main() ' Save colors so they can be restored when use finishes input. Dim dftForeColor As ConsoleColor = Console.ForegroundColor Dim dftBackColor As ConsoleColor = Console.BackgroundColor Dim continueFlag As Boolean = True Console.Clear() Do Dim newForeColor As ConsoleColor Dim newBackColor As ConsoleColor Dim foreColorSelection As Char = GetKeyPress("Select Text Color (B for Blue, R for Red, Y for Yellow): ", { "B"c, "R"c, "Y"c } ) Select Case foreColorSelection Case "B"c, "b"c newForeColor = ConsoleColor.DarkBlue Case "R"c, "r"c newForeColor = ConsoleColor.DarkRed Case "Y"c, "y"c newForeColor = ConsoleColor.DarkYellow End Select Dim backColorSelection As Char = GetKeyPress("Select Background Color (W for White, G for Green, M for Magenta): ", { "W"c, "G"c, "M"c }) Select Case backColorSelection Case "W"c, "w"c newBackColor = ConsoleColor.White Case "G"c, "g"c newBackColor = ConsoleColor.Green Case "M"c, "m"c newBackColor = ConsoleColor.Magenta End Select Console.WriteLine() Console.Write("Enter a message to display: ") Dim textToDisplay As String = Console.ReadLine() Console.WriteLine() Console.ForegroundColor = newForeColor Console.BackgroundColor = newBackColor Console.WriteLine(textToDisplay) Console.WriteLine() If Char.ToUpper(GetKeyPress("Display another message (Y/N): ", { "Y"c, "N"c } )) = "N" Then continueFlag = False End If ' Restore the default settings and clear the screen. Console.ForegroundColor = dftForeColor Console.BackgroundColor = dftBackColor Console.Clear() Loop While continueFlag End Sub Private Function GetKeyPress(msg As String, validChars() As Char) As Char Dim keyPressed As ConsoleKeyInfo Dim valid As Boolean = False Console.WriteLine() Do Console.Write(msg) keyPressed = Console.ReadKey() Console.WriteLine() If Array.Exists(validChars, Function(ch As Char) ch.Equals(Char.ToUpper(keypressed.KeyChar))) valid = True End If Loop While Not valid Return keyPressed.KeyChar End FunctionEnd Module

The example relies on a GetKeyPress method to validate the user's selection of a foreground and background color.

This example demonstrates the CursorLeft and CursorTop properties, and the SetCursorPosition and Clear methods. The example positions the cursor, which determines where the next write will occur, to draw a 5 character by 5 character rectangle using a combination of "+", "|", and "-" strings. Note that the rectangle could be drawn with fewer steps using a combination of other strings.

// This example demonstrates the // Console.CursorLeft and // Console.CursorTop properties, and the// Console.SetCursorPosition and // Console.Clear methods.using namespace System;int origRow;int origCol;void WriteAt( String^ s, int x, int y ){ try { Console::SetCursorPosition( origCol + x, origRow + y ); Console::Write( s ); } catch ( ArgumentOutOfRangeException^ e ) { Console::Clear(); Console::WriteLine( e->Message ); }}int main(){ // Clear the screen, then save the top and left coordinates. Console::Clear(); origRow = Console::CursorTop; origCol = Console::CursorLeft; // Draw the left side of a 5x5 rectangle, from top to bottom. WriteAt( "+", 0, 0 ); WriteAt( "|", 0, 1 ); WriteAt( "|", 0, 2 ); WriteAt( "|", 0, 3 ); WriteAt( "+", 0, 4 ); // Draw the bottom side, from left to right. WriteAt( "-", 1, 4 ); // shortcut: WriteAt("---", 1, 4) WriteAt( "-", 2, 4 ); // ... WriteAt( "-", 3, 4 ); // ... WriteAt( "+", 4, 4 ); // Draw the right side, from bottom to top. WriteAt( "|", 4, 3 ); WriteAt( "|", 4, 2 ); WriteAt( "|", 4, 1 ); WriteAt( "+", 4, 0 ); // Draw the top side, from right to left. WriteAt( "-", 3, 0 ); // shortcut: WriteAt("---", 1, 0) WriteAt( "-", 2, 0 ); // ... WriteAt( "-", 1, 0 ); // ... // WriteAt( "All done!", 0, 6 ); Console::WriteLine();}/*This example produces the following results:+---+| || || |+---+All done!*/

// This example demonstrates the// Console.CursorLeft and// Console.CursorTop properties, and the// Console.SetCursorPosition and// Console.Clear methods.using System;class Sample{ protected static int origRow; protected static int origCol; protected static void WriteAt(string s, int x, int y) { try { Console.SetCursorPosition(origCol+x, origRow+y); Console.Write(s); } catch (ArgumentOutOfRangeException e) { Console.Clear(); Console.WriteLine(e.Message); } } public static void Main() {// Clear the screen, then save the top and left coordinates. Console.Clear(); origRow = Console.CursorTop; origCol = Console.CursorLeft;// Draw the left side of a 5x5 rectangle, from top to bottom. WriteAt("+", 0, 0); WriteAt("|", 0, 1); WriteAt("|", 0, 2); WriteAt("|", 0, 3); WriteAt("+", 0, 4);// Draw the bottom side, from left to right. WriteAt("-", 1, 4); // shortcut: WriteAt("---", 1, 4) WriteAt("-", 2, 4); // ... WriteAt("-", 3, 4); // ... WriteAt("+", 4, 4);// Draw the right side, from bottom to top. WriteAt("|", 4, 3); WriteAt("|", 4, 2); WriteAt("|", 4, 1); WriteAt("+", 4, 0);// Draw the top side, from right to left. WriteAt("-", 3, 0); // shortcut: WriteAt("---", 1, 0) WriteAt("-", 2, 0); // ... WriteAt("-", 1, 0); // ...// WriteAt("All done!", 0, 6); Console.WriteLine(); }}/*This example produces the following results:+---+| || || |+---+All done!*/

// This example demonstrates the// Console.CursorLeft and// Console.CursorTop properties, and the// Console.SetCursorPosition and// Console.Clear methods.open System// Clear the screen, then save the top and left coordinates.Console.Clear()let origRow = Console.CursorToplet origCol = Console.CursorLeftlet writeAt s x y = try Console.SetCursorPosition(origCol + x, origRow + y) printfn $"%s{s}" with :? ArgumentOutOfRangeException as e -> Console.Clear() printfn $"{e.Message}"// Draw the left side of a 5x5 rectangle, from top to bottom.writeAt "+" 0 0writeAt "|" 0 1writeAt "|" 0 2writeAt "|" 0 3writeAt "+" 0 4// Draw the bottom side, from left to right.writeAt "-" 1 4 // shortcut: writeAt "---", 1, 4)writeAt "-" 2 4 // ...writeAt "-" 3 4 // ...writeAt "+" 4 4// Draw the right side, from bottom to top.writeAt "|" 4 3writeAt "|" 4 2writeAt "|" 4 1writeAt "+" 4 0// Draw the top side, from right to left.writeAt "-" 3 0 // shortcut: writeAt "---", 1, 0)writeAt "-" 2 0 // ...writeAt "-" 1 0 // ...writeAt "All done!" 0 6printfn ""// This example produces the following results://// +---+// | |// | |// | |// +---+//// All done!

' This example demonstrates the ' Console.CursorLeft and ' Console.CursorTop properties, and the' Console.SetCursorPosition and ' Console.Clear methods.Class Sample Protected Shared origRow As Integer Protected Shared origCol As Integer Protected Shared Sub WriteAt(s As String, x As Integer, y As Integer) Try Console.SetCursorPosition(origCol + x, origRow + y) Console.Write(s) Catch e As ArgumentOutOfRangeException Console.Clear() Console.WriteLine(e.Message) End Try End Sub Public Shared Sub Main() ' Clear the screen, then save the top and left coordinates. Console.Clear() origRow = Console.CursorTop origCol = Console.CursorLeft ' Draw the left side of a 5x5 rectangle, from top to bottom. WriteAt("+", 0, 0) WriteAt("|", 0, 1) WriteAt("|", 0, 2) WriteAt("|", 0, 3) WriteAt("+", 0, 4) ' Draw the bottom side, from left to right. WriteAt("-", 1, 4) ' shortcut: WriteAt("---", 1, 4) WriteAt("-", 2, 4) ' ... WriteAt("-", 3, 4) ' ... WriteAt("+", 4, 4) ' Draw the right side, from bottom to top. WriteAt("|", 4, 3) WriteAt("|", 4, 2) WriteAt("|", 4, 1) WriteAt("+", 4, 0) ' Draw the top side, from right to left. WriteAt("-", 3, 0) ' shortcut: WriteAt("---", 1, 0) WriteAt("-", 2, 0) ' ... WriteAt("-", 1, 0) ' ... ' WriteAt("All done!", 0, 6) Console.WriteLine() End SubEnd Class''This example produces the following results:''+---+'| |'| |'| |'+---+''All done!'

Remarks

Using the Clear method is equivalent invoking the MS-DOS cls command in the command prompt window. When the Clear method is called, the cursor automatically scrolls to the top-left corner of the window and the contents of the screen buffer are set to blanks using the current foreground background colors.

Applies to