Console.WindowLeft Property
Important
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Gets or sets the leftmost position of the console window area relative to the screen buffer.
public:
static property int WindowLeft { int get(); void set(int value); };
public static int WindowLeft { get; [System.Runtime.Versioning.SupportedOSPlatform("windows")] set; }
public static int WindowLeft { get; set; }
[<set: System.Runtime.Versioning.SupportedOSPlatform("windows")>]
static member WindowLeft : int with get, set
static member WindowLeft : int with get, set
Public Shared Property WindowLeft As Integer
The leftmost console window position measured in columns.
- Attributes
In a set operation, the value to be assigned is less than zero.
-or-
As a result of the assignment, WindowLeft plus WindowWidth would exceed BufferWidth.
Error reading or writing information.
The set operation is invoked on an operating system other than Windows.
The following example opens an 80-column console window and defines a buffer area that is 120 columns wide. It displays information on window and buffer size, and then waits for the user to press either the LEFT ARROW key or the RIGHT ARROW key. In the former case, it decrements the value of the WindowLeft property by one if the result is a legal value. In the latter case, it increases the value of the WindowLeft property by one if the result would be legal. Note that the example does not have to handle an ArgumentOutOfRangeException, because it checks that the value to be assigned to the WindowLeft property is not negative and does not cause the sum of the WindowLeft and WindowWidth properties to exceed the BufferWidth property value.
using namespace System;
void ShowConsoleStatistics()
{
Console::WriteLine("Console statistics:");
Console::WriteLine(" Buffer: {0} x {1}", Console::BufferHeight, Console::BufferWidth);
Console::WriteLine(" Window: {0} x {1}", Console::WindowHeight, Console::WindowWidth);
Console::WriteLine(" Window starts at {0}.", Console::WindowLeft);
Console::WriteLine("Press <- or -> to move window, Ctrl+C to exit.");
}
int main()
{
ConsoleKeyInfo key;
bool moved = false;
Console::BufferWidth = 120;
Console::Clear();
ShowConsoleStatistics();
do {
key = Console::ReadKey(true);
if (key.Key == ConsoleKey::LeftArrow)
{
int pos = Console::WindowLeft - 1;
if (pos >= 0 && pos + Console::WindowWidth <= Console::BufferWidth)
{
Console::WindowLeft = pos;
moved = true;
}
}
else if (key.Key == ConsoleKey::RightArrow)
{
int pos = Console::WindowLeft + 1;
if (pos + Console::WindowWidth <= Console::BufferWidth)
{
Console::WindowLeft = pos;
moved = true;
}
}
if (moved)
{
ShowConsoleStatistics();
moved = false;
}
Console::WriteLine();
} while (true);
}
using System;
public class Example
{
public static void Main()
{
ConsoleKeyInfo key;
bool moved = false;
Console.BufferWidth += 4;
Console.Clear();
ShowConsoleStatistics();
do
{
key = Console.ReadKey(true);
if (key.Key == ConsoleKey.LeftArrow)
{
int pos = Console.WindowLeft - 1;
if (pos >= 0 && pos + Console.WindowWidth <= Console.BufferWidth)
{
Console.WindowLeft = pos;
moved = true;
}
}
else if (key.Key == ConsoleKey.RightArrow)
{
int pos = Console.WindowLeft + 1;
if (pos + Console.WindowWidth <= Console.BufferWidth)
{
Console.WindowLeft = pos;
moved = true;
}
}
if (moved)
{
ShowConsoleStatistics();
moved = false;
}
Console.WriteLine();
} while (true);
}
private static void ShowConsoleStatistics()
{
Console.WriteLine("Console statistics:");
Console.WriteLine(" Buffer: {0} x {1}", Console.BufferHeight, Console.BufferWidth);
Console.WriteLine(" Window: {0} x {1}", Console.WindowHeight, Console.WindowWidth);
Console.WriteLine(" Window starts at {0}.", Console.WindowLeft);
Console.WriteLine("Press <- or -> to move window, Ctrl+C to exit.");
}
}
open System
let showConsoleStatistics () =
printfn "Console statistics:"
printfn $" Buffer: {Console.BufferHeight} x {Console.BufferWidth}"
printfn $" Window: {Console.WindowHeight} x {Console.WindowWidth}"
printfn $" Window starts at {Console.WindowLeft}."
printfn "Press <- or -> to move window, Ctrl+C to exit."
Console.BufferWidth <- Console.BufferWidth + 4
Console.Clear()
showConsoleStatistics ()
let mutable moved = false
while true do
let key = Console.ReadKey true
if key.Key = ConsoleKey.LeftArrow then
let pos = Console.WindowLeft - 1
if pos >= 0 && pos + Console.WindowWidth <= Console.BufferWidth then
Console.WindowLeft <- pos
moved <- true
elif key.Key = ConsoleKey.RightArrow then
let pos = Console.WindowLeft + 1
if pos + Console.WindowWidth <= Console.BufferWidth then
Console.WindowLeft <- pos
moved <- true
if moved then
showConsoleStatistics ()
moved <- false
printfn ""
Module Example
Public Sub Main()
Dim key As ConsoleKeyInfo
Dim moved As Boolean = False
Console.BufferWidth = 120
Console.Clear()
ShowConsoleStatistics()
Do While True
key = Console.ReadKey(True)
If key.Key = ConsoleKey.LeftArrow Then
Dim pos As Integer = Console.WindowLeft - 1
If pos >= 0 And pos + Console.WindowWidth <= Console.BufferWidth Then
Console.WindowLeft = pos
moved = True
End If
ElseIf key.Key = ConsoleKey.RightArrow Then
Dim pos As Integer = Console.WindowLeft + 1
If pos + Console.WindowWidth <= Console.BufferWidth Then
Console.WindowLeft = pos
moved = True
End If
End If
If moved Then ShowConsoleStatistics() : moved = False
Console.WriteLine()
Loop
End Sub
Private Sub ShowConsoleStatistics()
Console.WriteLine("Console statistics:")
Console.WriteLine(" Buffer: {0} x {1}", Console.BufferHeight, Console.BufferWidth)
Console.WriteLine(" Window: {0} x {1}", Console.WindowHeight, Console.WindowWidth)
Console.WriteLine(" Window starts at {0}.", Console.WindowLeft)
Console.WriteLine("Press <- or -> to move window, Ctrl+C to exit.")
End Sub
End Module
The console represents a rectangular window into a larger rectangular buffer area. Both the window and the buffer are measured vertically by their number of rows and horizontally by their number of columns. The dimensions of the buffer area are defined by the BufferHeight and BufferWidth properties. The dimensions of the console area are defined by the WindowHeight and WindowWidth properties. The WindowLeft property determines which column of the buffer area is displayed in the first column of the console window. The value of the WindowLeft property can range from 0 to BufferWidth - WindowWidth. Attempting to set it to a value outside that range throws an ArgumentOutOfRangeException.
When a console window first opens, the default value of the WindowLeft property is zero, which indicates that the first column shown by the console corresponds to the first column (the column at position zero) in the buffer area. The default width of both the console window and the buffer area is 80 columns. This means that the WindowLeft property can be modified only if the console window is made narrower or the buffer area is made wider.
Note that if the width of the buffer area exceeds the width of the console window, the value of the WindowLeft property is automatically adjusted when the user uses the horizontal scroll bar to define the window's relationship to the buffer area.
Attempting to set the value of the WindowLeft property when output is redirected throws an IOException exception. To prevent the exception, you can set the value of this property only if the IsOutputRedirected property returns false
.
Produit | Versions |
---|---|
.NET | Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9 |
.NET Framework | 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1 |
.NET Standard | 1.3, 1.4, 1.6, 2.0, 2.1 |
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