Bahasa

Console.Clear Metode

Definisi

Ruang nama:
System
Rakitan:
netstandard.dll, System.Console.dll
Rakitan:
System.Console.dll
Rakitan:
mscorlib.dll
Rakitan:
netstandard.dll
Sumber:
Console.cs
Sumber:
Console.cs
Sumber:
Console.cs
Sumber:
Console.cs
Sumber:
Console.cs

Menghapus buffer konsol dan jendela konsol yang sesuai dari informasi tampilan.

public:
 static void Clear();
[System.Runtime.Versioning.UnsupportedOSPlatform("android")]
[System.Runtime.Versioning.UnsupportedOSPlatform("ios")]
[System.Runtime.Versioning.UnsupportedOSPlatform("tvos")]
public static void Clear();
public static void Clear();
[<System.Runtime.Versioning.UnsupportedOSPlatform("android")>]
[<System.Runtime.Versioning.UnsupportedOSPlatform("ios")>]
[<System.Runtime.Versioning.UnsupportedOSPlatform("tvos")>]
static member Clear : unit -> unit
static member Clear : unit -> unit
Public Shared Sub Clear ()
Atribut
UnsupportedOSPlatformAttribute

Pengecualian

IOException

Terjadi kesalahan I/O.

Contoh

Contoh berikut menggunakan metode untuk menghapus konsol Clear sebelum menjalankan perulangan, meminta pengguna untuk memilih warna latar depan dan latar belakang dan memasukkan string untuk ditampilkan. Jika pengguna memilih untuk tidak keluar dari program, warna latar depan dan latar belakang asli konsol dipulihkan dan metode dipanggil Clear lagi sebelum mengeksekusi ulang perulangan.

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 System

let 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.ForegroundColor
let dftBackColor = Console.BackgroundColor
let mutable continueFlag = true
Console.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 Function
End Module

Contohnya bergantung pada GetKeyPress metode untuk memvalidasi pilihan pengguna dari warna latar depan dan latar belakang.

Contoh ini menunjukkan CursorLeft properti dan CursorTop , dan SetCursorPosition metode dan Clear . Contoh memposisikan kursor, yang menentukan di mana penulisan berikutnya akan terjadi, untuk menggambar persegi panjang 5 karakter dengan 5 karakter menggunakan kombinasi string "+", "|", dan "-". Perhatikan bahwa persegi panjang dapat digambar dengan lebih sedikit langkah menggunakan kombinasi string lain.

// 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.CursorTop
let origCol = Console.CursorLeft

let 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 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
printfn ""


// 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 Sub
End Class
'
'This example produces the following results:
'
'+---+
'|   |
'|   |
'|   |
'+---+
'
'All done!
'

Keterangan

Clear Menggunakan metode ini setara dengan memanggil perintah MS-DOS cls di jendela prompt perintah. Clear Ketika metode dipanggil, kursor secara otomatis menggulir ke sudut kiri atas jendela dan konten buffer layar diatur ke kosong menggunakan warna latar depan saat ini.

Note

Mencoba memanggil Clear metode ketika output aplikasi konsol dialihkan ke file melempar IOException. Untuk mencegah hal ini, selalu bungkus panggilan ke Clear metode dalam try... catch Blok.

Berlaku untuk