System.Console 作为带有输入行的日志 window
System.Console as a log window with input line
我正在编写一个控制台应用程序，它需要用户在文本滚动时在底行输入。这个想法是让文本滚动并在底部留下一个输入行。我想要文本编辑功能（箭头键、插入、删除等）。我也希望能够拥有静态 "status lines"（不受滚动影响的行）。
一个真实世界的例子是 Irssi：
在我的代码中，我连接到 NLog 并将其输出写入屏幕，同时还向用户提供输入行。它由 "pausing input" 在写入时完成：使用 Console.MoveBufferArea 向上移动文本、禁用光标、重新定位光标、写入日志文本、将光标重新定位回输入行并启用光标。差不多可以了，但是有一些问题：
- 速度很慢。在我写 20-30 行的情况下，应用程序会显着变慢。 （可以通过缓冲传入解决，但不会解决滚动速度问题。）
- 溢出的行（即异常堆栈跟踪）在屏幕的最底部留下一行。
- 随着文本向上滚动，溢出的行会（部分）被覆盖。这也会弄乱输入行。
- 滚动up/down 不起作用。
有图书馆可以帮我做这件事吗？
如果不是那么我该如何解决速度问题？如何修复滚动？
首选跨平台解决方案。
public class InputConsole
{
private static readonly object _bufferLock = new object();
private static int _windowWidth = Console.BufferWidth;
private static int _windowHeight = Console.BufferHeight;
private static int _windowLeft = Console.WindowLeft;
private static int _windowTop = Console.WindowTop;
public InputConsole()
{
MethodCallTarget target = new MethodCallTarget();
target.ClassName = typeof(InputConsole).AssemblyQualifiedName;
target.MethodName = "LogMethod";
target.Parameters.Add(new MethodCallParameter("${level}"));
target.Parameters.Add(new MethodCallParameter("${message}"));
target.Parameters.Add(new MethodCallParameter("${exception:format=tostring}"));
target.Parameters.Add(new MethodCallParameter("[${logger:shortName=true}]"));
SimpleConfigurator.ConfigureForTargetLogging(target, LogLevel.Trace);
try
{
Console.SetWindowSize(180, 50);
Console.SetBufferSize(180, 50);
_windowWidth = Console.BufferWidth;
_windowHeight = Console.BufferHeight;
}
catch (Exception exception)
{
Console.WriteLine("Unable to resize console: " + exception);
}
}
public void Run()
{
string input;
do
{
lock (_bufferLock)
{
Console.SetCursorPosition(0, _windowHeight - 1);
Console.Write("Command: ");
Console.CursorVisible = true;
}
Console.BackgroundColor = ConsoleColor.Black;
Console.ForegroundColor = ConsoleColor.Yellow;
input = Console.ReadLine();
lock (_bufferLock)
{
Console.CursorVisible = false;
}
} while (!string.Equals(input, "quit", StringComparison.OrdinalIgnoreCase));
}
public static void LogMethod(string level, string message, string exception, string caller)
{
if (Console.BufferHeight == _windowHeight)
Console.MoveBufferArea(_windowLeft, _windowTop + 1, Console.BufferWidth, Console.BufferHeight - 2, _windowLeft, _windowTop);
var fgColor = ConsoleColor.White;
var bgColor = ConsoleColor.Black;
switch (level.ToUpper())
{
case "TRACE":
fgColor = ConsoleColor.DarkGray;
break;
case "DEBUG":
fgColor = ConsoleColor.Gray;
break;
case "INFO":
fgColor = ConsoleColor.White;
break;
case "WARNING":
fgColor = ConsoleColor.Cyan;
break;
case "ERROR":
fgColor = ConsoleColor.White;
bgColor = ConsoleColor.Red;
break;
}
var str = string.Format("({0}) {1} {2} {3}", level.ToUpper(), caller, message, exception);
WriteAt(_windowLeft, _windowHeight - 3, str, fgColor, bgColor);
}
public static void WriteAt(int left, int top, string s, ConsoleColor foregroundColor = ConsoleColor.White, ConsoleColor backgroundColor = ConsoleColor.Black)
{
lock (_bufferLock)
{
var currentBackgroundColor = Console.BackgroundColor;
var currentForegroundColor = Console.ForegroundColor;
Console.BackgroundColor = backgroundColor;
Console.ForegroundColor = foregroundColor;
int currentLeft = Console.CursorLeft;
int currentTop = Console.CursorTop;
var currentVisible = Console.CursorVisible;
Console.CursorVisible = false;
Console.SetCursorPosition(left, top);
Console.Write(s);
Console.SetCursorPosition(currentLeft, currentTop);
Console.CursorVisible = currentVisible;
Console.BackgroundColor = currentBackgroundColor;
Console.ForegroundColor = currentForegroundColor;
}
}
}
在 Windows 中对文本控制台进行进一步研究 我似乎很难让它运行得更快。通过具有较低重绘率（小于 WriteConsoleOutput）的自定义实现，我能够获得超过 Console.WriteLine.
10 倍的速度提升
然而，由于 Console.WriteLine 强制执行 "scroll everything when we reach bottom"，我使用的是 Console.MoveBufferArea。测试表明，我对 MoveBufferArea 的实现（包含在我的原始问题中）比 Console.WriteLine 慢了大约 90 倍。然而，通过使用 WriteConsoleOutput 的新实现，我的速度比 MoveBufferedArea.
提高了 1356 倍
由于很难找到有关它的信息，我在 blog post 中详细说明了我的发现。我还将代码附加到此答案以供后代使用。
我写了一个 class 允许我滚动单个框。我还实现了一个线路输入系统来模拟标准 Console.ReadLine();。请注意，缺少此实现 home/end-support（尽管很容易修复）。
请注意，要从中获得任何速度提升，您必须设置 box.AutoRedraw = false; 并定期手动调用 box.Draw();。使用 box.AutoRedraw = true;（在每个 Write() 上调用 Draw()）这个解决方案实际上比 Console.WriteLine 慢 30 倍，比 MoveBufferArea 快 3 倍。
使用示例：
_logBox = new InputConsoleBox(0, 0, (short)Console.BufferWidth, (short)(Console.BufferHeight - 2), InputConsoleBox.Colors.LightWhite, InputConsoleBox.Colors.Black);
_statusBox = new InputConsoleBox(0, (short)(Console.BufferHeight - 3), (short)Console.BufferWidth, 1, InputConsoleBox.Colors.LightYellow, InputConsoleBox.Colors.DarkBlue);
_inputBox = new InputConsoleBox(0, (short)(Console.BufferHeight - 2), (short)Console.BufferWidth, 1, InputConsoleBox.Colors.LightYellow, InputConsoleBox.Colors.Black);
_statusBox.WriteLine("Hey there!");
_inputBox.InputPrompt = "Command: ";
// If you are okay with some slight flickering this is an easy way to set up a refresh timer
_logBox.AutoDraw = false;
_redrawTask = Task.Factory.StartNew(async () =>
{
while (true)
{
await Task.Delay(100);
if (_logBox.IsDirty)
_logBox.Draw();
}
});
// Line input box
var line = _inputBox.ReadLine(); // Blocking while waiting for <enter>
代码：
using System;
using System.Collections.Generic;
using System.IO;
using System.Runtime.InteropServices;
using System.Threading;
using Microsoft.Win32.SafeHandles;
public class InputConsoleBox
{
#region Output
#region Win32 interop
private const UInt32 STD_OUTPUT_HANDLE = unchecked((UInt32)(-11));
private const UInt32 STD_ERROR_HANDLE = unchecked((UInt32)(-12));
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
private static extern IntPtr GetStdHandle(UInt32 type);
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
private static extern SafeFileHandle CreateFile(
string fileName,
[MarshalAs(UnmanagedType.U4)] uint fileAccess,
[MarshalAs(UnmanagedType.U4)] uint fileShare,
IntPtr securityAttributes,
[MarshalAs(UnmanagedType.U4)] FileMode creationDisposition,
[MarshalAs(UnmanagedType.U4)] int flags,
IntPtr template);
[DllImport("kernel32.dll", SetLastError = true)]
private static extern bool WriteConsoleOutput(
SafeFileHandle hConsoleOutput,
CharInfo[] lpBuffer,
Coord dwBufferSize,
Coord dwBufferCoord,
ref SmallRect lpWriteRegion);
[StructLayout(LayoutKind.Sequential)]
private struct Coord
{
public short X;
public short Y;
public Coord(short X, short Y)
{
this.X = X;
this.Y = Y;
}
};
[StructLayout(LayoutKind.Explicit)]
private struct CharUnion
{
[FieldOffset(0)]
public char UnicodeChar;
[FieldOffset(0)]
public byte AsciiChar;
}
[StructLayout(LayoutKind.Explicit)]
private struct CharInfo
{
[FieldOffset(0)]
public CharUnion Char;
[FieldOffset(2)]
public ushort Attributes;
public CharInfo(char @char, ushort attributes)
{
this.Char = new CharUnion();
Char.UnicodeChar = @char;
Attributes = attributes;
}
}
[StructLayout(LayoutKind.Sequential)]
private struct SmallRect
{
public short Left;
public short Top;
public short Right;
public short Bottom;
}
#endregion
#region Colors Enum
private const int HighIntensity = 0x0008;
private const ushort COMMON_LVB_LEADING_BYTE = 0x0100;
private const ushort COMMON_LVB_TRAILING_BYTE = 0x0200;
private const ushort COMMON_LVB_GRID_HORIZONTAL = 0x0400;
private const ushort COMMON_LVB_GRID_LVERTICAL = 0x0800;
private const ushort COMMON_LVB_GRID_RVERTICAL = 0x1000;
private const ushort COMMON_LVB_REVERSE_VIDEO = 0x4000;
private const ushort COMMON_LVB_UNDERSCORE = 0x8000;
private const ushort COMMON_LVB_SBCSDBCS = 0x0300;
[Flags]
public enum Colors : int
{
Black = 0x0000,
DarkBlue = 0x0001,
DarkGreen = 0x0002,
DarkRed = 0x0004,
Gray = DarkBlue | DarkGreen | DarkRed,
DarkYellow = DarkRed | DarkGreen,
DarkPurple = DarkRed | DarkBlue,
DarkCyan = DarkGreen | DarkBlue,
LightBlue = DarkBlue | HighIntensity,
LightGreen = DarkGreen | HighIntensity,
LightRed = DarkRed | HighIntensity,
LightWhite = Gray | HighIntensity,
LightYellow = DarkYellow | HighIntensity,
LightPurple = DarkPurple | HighIntensity,
LightCyan = DarkCyan | HighIntensity
}
#endregion // Colors Enum
private readonly CharInfo[] _buffer;
private readonly List<CharInfo> _tmpBuffer;
private readonly short _left;
private readonly short _top;
private readonly short _width;
private readonly short _height;
private ushort _defaultColor;
private int _cursorLeft;
private int _cursorTop;
private static SafeFileHandle _safeFileHandle;
/// <summary>
/// Automatically draw to console.
/// Unset this if you want to manually control when (and what order) boxes are writen to consoles - or you want to batch some stuff.
/// You must manually call <c>Draw()</c> to write to console.
/// </summary>
public bool AutoDraw = true;
public bool IsDirty { get; private set; }
public InputConsoleBox(short left, short top, short width, short height, Colors defaultForegroundColor = Colors.Gray, Colors defaultBackgroundColor = Colors.Black)
{
if (left < 0 || top < 0 || left + width > Console.BufferWidth || top + height > Console.BufferHeight)
throw new Exception(string.Format("Attempting to create a box {0},{1}->{2},{3} that is out of buffer bounds 0,0->{4},{5}", left, top, left + width, top + height, Console.BufferWidth, Console.BufferHeight));
_left = left;
_top = top;
_width = width;
_height = height;
_buffer = new CharInfo[_width * _height];
_defaultColor = CombineColors(defaultForegroundColor, defaultBackgroundColor);
_tmpBuffer = new List<CharInfo>(_width * _height); // Assumption that we won't be writing much more than a screenful (backbufferfull) in every write operation
//SafeFileHandle h = CreateFile("CONOUT$", 0x40000000, 2, IntPtr.Zero, FileMode.Open, 0, IntPtr.Zero);
if (_safeFileHandle == null)
{
var stdOutputHandle = GetStdHandle(STD_OUTPUT_HANDLE);
_safeFileHandle = new SafeFileHandle(stdOutputHandle, false);
}
Clear();
Draw();
}
public void Clear()
{
for (int y = 0; y < _height; y++)
{
for (int x = 0; x < _width; x++)
{
var i = (y * _width) + x;
_buffer[i].Char.UnicodeChar = ' ';
_buffer[i].Attributes = _defaultColor;
}
}
IsDirty = true;
// Update screen
if (AutoDraw)
Draw();
}
public void Draw()
{
IsDirty = false;
var rect = new SmallRect() { Left = _left, Top = _top, Right = (short)(_left + _width), Bottom = (short)(_top + _height) };
bool b = WriteConsoleOutput(_safeFileHandle, _buffer,
new Coord(_width, _height),
new Coord(0, 0), ref rect);
}
private static ushort CombineColors(Colors foreColor, Colors backColor)
{
return (ushort)((int)foreColor + (((int)backColor) << 4));
}
public void SetCursorPosition(int left, int top)
{
if (left >= _width || top >= _height)
throw new Exception(string.Format("Position out of bounds attempting to set cursor at box pos {0},{1} when box size is only {2},{3}.", left, top, _width, _height));
_cursorLeft = left;
_cursorTop = top;
}
public void SetCursorBlink(int left, int top, bool state)
{
Console.SetCursorPosition(left, top);
Console.CursorVisible = state;
//// Does not work
//var i = (top * _width) + left;
//if (state)
// _buffer[i].Attributes = (ushort)((int)_buffer[i].Attributes & ~(int)COMMON_LVB_UNDERSCORE);
//else
// _buffer[i].Attributes = (ushort)((int)_buffer[i].Attributes | (int)COMMON_LVB_UNDERSCORE);
//if (AutoDraw)
// Draw();
}
public void WriteLine(string line, Colors fgColor, Colors bgColor)
{
var c = _defaultColor;
_defaultColor = CombineColors(fgColor, bgColor);
WriteLine(line);
_defaultColor = c;
}
public void WriteLine(string line)
{
Write(line + "\n");
}
public void Write(string text)
{
Write(text.ToCharArray());
}
public void Write(char[] text)
{
IsDirty = true;
_tmpBuffer.Clear();
bool newLine = false;
// Old-school! Could definitively have been done more easily with regex. :)
var col = 0;
var row = -1;
for (int i = 0; i < text.Length; i++)
{
// Detect newline
if (text[i] == '\n')
newLine = true;
if (text[i] == '\r')
{
newLine = true;
// Skip following \n
if (i + 1 < text.Length && text[i] == '\n')
i++;
}
// Keep track of column and row
col++;
if (col == _width)
{
col = 0;
row++;
if (newLine) // Last character was newline? Skip filling the whole next line with empty
{
newLine = false;
continue;
}
}
// If we are newlining we need to fill the remaining with blanks
if (newLine)
{
newLine = false;
for (int i2 = col; i2 <= _width; i2++)
{
_tmpBuffer.Add(new CharInfo(' ', _defaultColor));
}
col = 0;
row++;
continue;
}
if (i >= text.Length)
break;
// Add character
_tmpBuffer.Add(new CharInfo(text[i], _defaultColor));
}
var cursorI = (_cursorTop * _width) + _cursorLeft;
// Get our end position
var end = cursorI + _tmpBuffer.Count;
// If we are overflowing (scrolling) then we need to complete our last line with spaces (align buffer with line ending)
if (end > _buffer.Length && col != 0)
{
for (int i = col; i <= _width; i++)
{
_tmpBuffer.Add(new CharInfo(' ', _defaultColor));
}
col = 0;
row++;
}
// Chop start of buffer to fit into destination buffer
if (_tmpBuffer.Count > _buffer.Length)
_tmpBuffer.RemoveRange(0, _tmpBuffer.Count - _buffer.Length);
// Convert to array so we can batch copy
var tmpArray = _tmpBuffer.ToArray();
// Are we going to write outside of buffer?
end = cursorI + _tmpBuffer.Count;
var scrollUp = 0;
if (end > _buffer.Length)
{
scrollUp = end - _buffer.Length;
}
// Scroll up
if (scrollUp > 0)
{
Array.Copy(_buffer, scrollUp, _buffer, 0, _buffer.Length - scrollUp);
cursorI -= scrollUp;
}
var lastPos = Math.Min(_buffer.Length, cursorI + tmpArray.Length);
var firstPos = lastPos - tmpArray.Length;
// Copy new data in
Array.Copy(tmpArray, 0, _buffer, firstPos, tmpArray.Length);
// Set new cursor position
_cursorLeft = col;
_cursorTop = Math.Min(_height, _cursorTop + row + 1);
// Write to main buffer
if (AutoDraw)
Draw();
}
#endregion
#region Input
private string _currentInputBuffer = "";
private string _inputPrompt;
private int _inputCursorPos = 0;
private int _inputFrameStart = 0;
// Not used because COMMON_LVB_UNDERSCORE doesn't work
//private bool _inputCursorState = false;
//private int _inputCursorStateChange = 0;
private int _cursorBlinkLeft = 0;
private int _cursorBlinkTop = 0;
public string InputPrompt
{
get { return _inputPrompt; }
set
{
_inputPrompt = value;
ResetInput();
}
}
private void ResetInput()
{
SetCursorPosition(0, 0);
_inputCursorPos = Math.Min(_currentInputBuffer.Length, _inputCursorPos);
var inputPrompt = InputPrompt + "[" + _currentInputBuffer.Length + "] ";
// What is the max length we can write?
var maxLen = _width - inputPrompt.Length;
if (maxLen < 0)
return;
if (_inputCursorPos > _inputFrameStart + maxLen)
_inputFrameStart = _inputCursorPos - maxLen;
if (_inputCursorPos < _inputFrameStart)
_inputFrameStart = _inputCursorPos;
_cursorBlinkLeft = inputPrompt.Length + _inputCursorPos - _inputFrameStart;
//if (_currentInputBuffer.Length - _inputFrameStart < maxLen)
// _inputFrameStart--;
// Write and pad the end
var str = inputPrompt + _currentInputBuffer.Substring(_inputFrameStart, Math.Min(_currentInputBuffer.Length - _inputFrameStart, maxLen));
var spaceLen = _width - str.Length;
Write(str + (spaceLen > 0 ? new String(' ', spaceLen) : ""));
UpdateCursorBlink(true);
}
private void UpdateCursorBlink(bool force)
{
// Since COMMON_LVB_UNDERSCORE doesn't work we won't be controlling blink
//// Blink the cursor
//if (Environment.TickCount > _inputCursorStateChange)
//{
// _inputCursorStateChange = Environment.TickCount + 250;
// _inputCursorState = !_inputCursorState;
// force = true;
//}
//if (force)
// SetCursorBlink(_cursorBlinkLeft, _cursorBlinkTop, _inputCursorState);
SetCursorBlink(_left + _cursorBlinkLeft, _top + _cursorBlinkTop, true);
}
public string ReadLine()
{
Console.CursorVisible = false;
Clear();
ResetInput();
while (true)
{
Thread.Sleep(50);
while (Console.KeyAvailable)
{
var key = Console.ReadKey(true);
switch (key.Key)
{
case ConsoleKey.Enter:
{
var ret = _currentInputBuffer;
_inputCursorPos = 0;
_currentInputBuffer = "";
return ret;
break;
}
case ConsoleKey.LeftArrow:
{
_inputCursorPos = Math.Max(0, _inputCursorPos - 1);
break;
}
case ConsoleKey.RightArrow:
{
_inputCursorPos = Math.Min(_currentInputBuffer.Length, _inputCursorPos + 1);
break;
}
case ConsoleKey.Backspace:
{
if (_inputCursorPos > 0)
{
_inputCursorPos--;
_currentInputBuffer = _currentInputBuffer.Remove(_inputCursorPos, 1);
}
break;
}
case ConsoleKey.Delete:
{
if (_inputCursorPos < _currentInputBuffer.Length - 1)
_currentInputBuffer = _currentInputBuffer.Remove(_inputCursorPos, 1);
break;
}
default:
{
var pos = _inputCursorPos;
//if (_inputCursorPos == _currentInputBuffer.Length)
_inputCursorPos++;
_currentInputBuffer = _currentInputBuffer.Insert(pos, key.KeyChar.ToString());
break;
}
}
ResetInput();
}
// COMMON_LVB_UNDERSCORE doesn't work so we use Consoles default cursor
//UpdateCursorBlink(false);
}
}
#endregion
}
我正在编写一个控制台应用程序，它需要用户在文本滚动时在底行输入。这个想法是让文本滚动并在底部留下一个输入行。我想要文本编辑功能（箭头键、插入、删除等）。我也希望能够拥有静态 "status lines"（不受滚动影响的行）。
一个真实世界的例子是 Irssi：
在我的代码中，我连接到 NLog 并将其输出写入屏幕，同时还向用户提供输入行。它由 "pausing input" 在写入时完成：使用 Console.MoveBufferArea 向上移动文本、禁用光标、重新定位光标、写入日志文本、将光标重新定位回输入行并启用光标。差不多可以了，但是有一些问题：
- 速度很慢。在我写 20-30 行的情况下，应用程序会显着变慢。 （可以通过缓冲传入解决，但不会解决滚动速度问题。）
- 溢出的行（即异常堆栈跟踪）在屏幕的最底部留下一行。
- 随着文本向上滚动，溢出的行会（部分）被覆盖。这也会弄乱输入行。
- 滚动up/down 不起作用。
有图书馆可以帮我做这件事吗？ 如果不是那么我该如何解决速度问题？如何修复滚动？
首选跨平台解决方案。
public class InputConsole
{
private static readonly object _bufferLock = new object();
private static int _windowWidth = Console.BufferWidth;
private static int _windowHeight = Console.BufferHeight;
private static int _windowLeft = Console.WindowLeft;
private static int _windowTop = Console.WindowTop;
public InputConsole()
{
MethodCallTarget target = new MethodCallTarget();
target.ClassName = typeof(InputConsole).AssemblyQualifiedName;
target.MethodName = "LogMethod";
target.Parameters.Add(new MethodCallParameter("${level}"));
target.Parameters.Add(new MethodCallParameter("${message}"));
target.Parameters.Add(new MethodCallParameter("${exception:format=tostring}"));
target.Parameters.Add(new MethodCallParameter("[${logger:shortName=true}]"));
SimpleConfigurator.ConfigureForTargetLogging(target, LogLevel.Trace);
try
{
Console.SetWindowSize(180, 50);
Console.SetBufferSize(180, 50);
_windowWidth = Console.BufferWidth;
_windowHeight = Console.BufferHeight;
}
catch (Exception exception)
{
Console.WriteLine("Unable to resize console: " + exception);
}
}
public void Run()
{
string input;
do
{
lock (_bufferLock)
{
Console.SetCursorPosition(0, _windowHeight - 1);
Console.Write("Command: ");
Console.CursorVisible = true;
}
Console.BackgroundColor = ConsoleColor.Black;
Console.ForegroundColor = ConsoleColor.Yellow;
input = Console.ReadLine();
lock (_bufferLock)
{
Console.CursorVisible = false;
}
} while (!string.Equals(input, "quit", StringComparison.OrdinalIgnoreCase));
}
public static void LogMethod(string level, string message, string exception, string caller)
{
if (Console.BufferHeight == _windowHeight)
Console.MoveBufferArea(_windowLeft, _windowTop + 1, Console.BufferWidth, Console.BufferHeight - 2, _windowLeft, _windowTop);
var fgColor = ConsoleColor.White;
var bgColor = ConsoleColor.Black;
switch (level.ToUpper())
{
case "TRACE":
fgColor = ConsoleColor.DarkGray;
break;
case "DEBUG":
fgColor = ConsoleColor.Gray;
break;
case "INFO":
fgColor = ConsoleColor.White;
break;
case "WARNING":
fgColor = ConsoleColor.Cyan;
break;
case "ERROR":
fgColor = ConsoleColor.White;
bgColor = ConsoleColor.Red;
break;
}
var str = string.Format("({0}) {1} {2} {3}", level.ToUpper(), caller, message, exception);
WriteAt(_windowLeft, _windowHeight - 3, str, fgColor, bgColor);
}
public static void WriteAt(int left, int top, string s, ConsoleColor foregroundColor = ConsoleColor.White, ConsoleColor backgroundColor = ConsoleColor.Black)
{
lock (_bufferLock)
{
var currentBackgroundColor = Console.BackgroundColor;
var currentForegroundColor = Console.ForegroundColor;
Console.BackgroundColor = backgroundColor;
Console.ForegroundColor = foregroundColor;
int currentLeft = Console.CursorLeft;
int currentTop = Console.CursorTop;
var currentVisible = Console.CursorVisible;
Console.CursorVisible = false;
Console.SetCursorPosition(left, top);
Console.Write(s);
Console.SetCursorPosition(currentLeft, currentTop);
Console.CursorVisible = currentVisible;
Console.BackgroundColor = currentBackgroundColor;
Console.ForegroundColor = currentForegroundColor;
}
}
}
在 Windows 中对文本控制台进行进一步研究 我似乎很难让它运行得更快。通过具有较低重绘率（小于 WriteConsoleOutput）的自定义实现，我能够获得超过 Console.WriteLine.
10 倍的速度提升然而，由于 Console.WriteLine 强制执行 "scroll everything when we reach bottom"，我使用的是 Console.MoveBufferArea。测试表明，我对 MoveBufferArea 的实现（包含在我的原始问题中）比 Console.WriteLine 慢了大约 90 倍。然而，通过使用 WriteConsoleOutput 的新实现，我的速度比 MoveBufferedArea.
提高了 1356 倍由于很难找到有关它的信息，我在 blog post 中详细说明了我的发现。我还将代码附加到此答案以供后代使用。
我写了一个 class 允许我滚动单个框。我还实现了一个线路输入系统来模拟标准 Console.ReadLine();。请注意，缺少此实现 home/end-support（尽管很容易修复）。
请注意，要从中获得任何速度提升，您必须设置 box.AutoRedraw = false; 并定期手动调用 box.Draw();。使用 box.AutoRedraw = true;（在每个 Write() 上调用 Draw()）这个解决方案实际上比 Console.WriteLine 慢 30 倍，比 MoveBufferArea 快 3 倍。
使用示例：
_logBox = new InputConsoleBox(0, 0, (short)Console.BufferWidth, (short)(Console.BufferHeight - 2), InputConsoleBox.Colors.LightWhite, InputConsoleBox.Colors.Black);
_statusBox = new InputConsoleBox(0, (short)(Console.BufferHeight - 3), (short)Console.BufferWidth, 1, InputConsoleBox.Colors.LightYellow, InputConsoleBox.Colors.DarkBlue);
_inputBox = new InputConsoleBox(0, (short)(Console.BufferHeight - 2), (short)Console.BufferWidth, 1, InputConsoleBox.Colors.LightYellow, InputConsoleBox.Colors.Black);
_statusBox.WriteLine("Hey there!");
_inputBox.InputPrompt = "Command: ";
// If you are okay with some slight flickering this is an easy way to set up a refresh timer
_logBox.AutoDraw = false;
_redrawTask = Task.Factory.StartNew(async () =>
{
while (true)
{
await Task.Delay(100);
if (_logBox.IsDirty)
_logBox.Draw();
}
});
// Line input box
var line = _inputBox.ReadLine(); // Blocking while waiting for <enter>
代码：
using System;
using System.Collections.Generic;
using System.IO;
using System.Runtime.InteropServices;
using System.Threading;
using Microsoft.Win32.SafeHandles;
public class InputConsoleBox
{
#region Output
#region Win32 interop
private const UInt32 STD_OUTPUT_HANDLE = unchecked((UInt32)(-11));
private const UInt32 STD_ERROR_HANDLE = unchecked((UInt32)(-12));
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
private static extern IntPtr GetStdHandle(UInt32 type);
[DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
private static extern SafeFileHandle CreateFile(
string fileName,
[MarshalAs(UnmanagedType.U4)] uint fileAccess,
[MarshalAs(UnmanagedType.U4)] uint fileShare,
IntPtr securityAttributes,
[MarshalAs(UnmanagedType.U4)] FileMode creationDisposition,
[MarshalAs(UnmanagedType.U4)] int flags,
IntPtr template);
[DllImport("kernel32.dll", SetLastError = true)]
private static extern bool WriteConsoleOutput(
SafeFileHandle hConsoleOutput,
CharInfo[] lpBuffer,
Coord dwBufferSize,
Coord dwBufferCoord,
ref SmallRect lpWriteRegion);
[StructLayout(LayoutKind.Sequential)]
private struct Coord
{
public short X;
public short Y;
public Coord(short X, short Y)
{
this.X = X;
this.Y = Y;
}
};
[StructLayout(LayoutKind.Explicit)]
private struct CharUnion
{
[FieldOffset(0)]
public char UnicodeChar;
[FieldOffset(0)]
public byte AsciiChar;
}
[StructLayout(LayoutKind.Explicit)]
private struct CharInfo
{
[FieldOffset(0)]
public CharUnion Char;
[FieldOffset(2)]
public ushort Attributes;
public CharInfo(char @char, ushort attributes)
{
this.Char = new CharUnion();
Char.UnicodeChar = @char;
Attributes = attributes;
}
}
[StructLayout(LayoutKind.Sequential)]
private struct SmallRect
{
public short Left;
public short Top;
public short Right;
public short Bottom;
}
#endregion
#region Colors Enum
private const int HighIntensity = 0x0008;
private const ushort COMMON_LVB_LEADING_BYTE = 0x0100;
private const ushort COMMON_LVB_TRAILING_BYTE = 0x0200;
private const ushort COMMON_LVB_GRID_HORIZONTAL = 0x0400;
private const ushort COMMON_LVB_GRID_LVERTICAL = 0x0800;
private const ushort COMMON_LVB_GRID_RVERTICAL = 0x1000;
private const ushort COMMON_LVB_REVERSE_VIDEO = 0x4000;
private const ushort COMMON_LVB_UNDERSCORE = 0x8000;
private const ushort COMMON_LVB_SBCSDBCS = 0x0300;
[Flags]
public enum Colors : int
{
Black = 0x0000,
DarkBlue = 0x0001,
DarkGreen = 0x0002,
DarkRed = 0x0004,
Gray = DarkBlue | DarkGreen | DarkRed,
DarkYellow = DarkRed | DarkGreen,
DarkPurple = DarkRed | DarkBlue,
DarkCyan = DarkGreen | DarkBlue,
LightBlue = DarkBlue | HighIntensity,
LightGreen = DarkGreen | HighIntensity,
LightRed = DarkRed | HighIntensity,
LightWhite = Gray | HighIntensity,
LightYellow = DarkYellow | HighIntensity,
LightPurple = DarkPurple | HighIntensity,
LightCyan = DarkCyan | HighIntensity
}
#endregion // Colors Enum
private readonly CharInfo[] _buffer;
private readonly List<CharInfo> _tmpBuffer;
private readonly short _left;
private readonly short _top;
private readonly short _width;
private readonly short _height;
private ushort _defaultColor;
private int _cursorLeft;
private int _cursorTop;
private static SafeFileHandle _safeFileHandle;
/// <summary>
/// Automatically draw to console.
/// Unset this if you want to manually control when (and what order) boxes are writen to consoles - or you want to batch some stuff.
/// You must manually call <c>Draw()</c> to write to console.
/// </summary>
public bool AutoDraw = true;
public bool IsDirty { get; private set; }
public InputConsoleBox(short left, short top, short width, short height, Colors defaultForegroundColor = Colors.Gray, Colors defaultBackgroundColor = Colors.Black)
{
if (left < 0 || top < 0 || left + width > Console.BufferWidth || top + height > Console.BufferHeight)
throw new Exception(string.Format("Attempting to create a box {0},{1}->{2},{3} that is out of buffer bounds 0,0->{4},{5}", left, top, left + width, top + height, Console.BufferWidth, Console.BufferHeight));
_left = left;
_top = top;
_width = width;
_height = height;
_buffer = new CharInfo[_width * _height];
_defaultColor = CombineColors(defaultForegroundColor, defaultBackgroundColor);
_tmpBuffer = new List<CharInfo>(_width * _height); // Assumption that we won't be writing much more than a screenful (backbufferfull) in every write operation
//SafeFileHandle h = CreateFile("CONOUT$", 0x40000000, 2, IntPtr.Zero, FileMode.Open, 0, IntPtr.Zero);
if (_safeFileHandle == null)
{
var stdOutputHandle = GetStdHandle(STD_OUTPUT_HANDLE);
_safeFileHandle = new SafeFileHandle(stdOutputHandle, false);
}
Clear();
Draw();
}
public void Clear()
{
for (int y = 0; y < _height; y++)
{
for (int x = 0; x < _width; x++)
{
var i = (y * _width) + x;
_buffer[i].Char.UnicodeChar = ' ';
_buffer[i].Attributes = _defaultColor;
}
}
IsDirty = true;
// Update screen
if (AutoDraw)
Draw();
}
public void Draw()
{
IsDirty = false;
var rect = new SmallRect() { Left = _left, Top = _top, Right = (short)(_left + _width), Bottom = (short)(_top + _height) };
bool b = WriteConsoleOutput(_safeFileHandle, _buffer,
new Coord(_width, _height),
new Coord(0, 0), ref rect);
}
private static ushort CombineColors(Colors foreColor, Colors backColor)
{
return (ushort)((int)foreColor + (((int)backColor) << 4));
}
public void SetCursorPosition(int left, int top)
{
if (left >= _width || top >= _height)
throw new Exception(string.Format("Position out of bounds attempting to set cursor at box pos {0},{1} when box size is only {2},{3}.", left, top, _width, _height));
_cursorLeft = left;
_cursorTop = top;
}
public void SetCursorBlink(int left, int top, bool state)
{
Console.SetCursorPosition(left, top);
Console.CursorVisible = state;
//// Does not work
//var i = (top * _width) + left;
//if (state)
// _buffer[i].Attributes = (ushort)((int)_buffer[i].Attributes & ~(int)COMMON_LVB_UNDERSCORE);
//else
// _buffer[i].Attributes = (ushort)((int)_buffer[i].Attributes | (int)COMMON_LVB_UNDERSCORE);
//if (AutoDraw)
// Draw();
}
public void WriteLine(string line, Colors fgColor, Colors bgColor)
{
var c = _defaultColor;
_defaultColor = CombineColors(fgColor, bgColor);
WriteLine(line);
_defaultColor = c;
}
public void WriteLine(string line)
{
Write(line + "\n");
}
public void Write(string text)
{
Write(text.ToCharArray());
}
public void Write(char[] text)
{
IsDirty = true;
_tmpBuffer.Clear();
bool newLine = false;
// Old-school! Could definitively have been done more easily with regex. :)
var col = 0;
var row = -1;
for (int i = 0; i < text.Length; i++)
{
// Detect newline
if (text[i] == '\n')
newLine = true;
if (text[i] == '\r')
{
newLine = true;
// Skip following \n
if (i + 1 < text.Length && text[i] == '\n')
i++;
}
// Keep track of column and row
col++;
if (col == _width)
{
col = 0;
row++;
if (newLine) // Last character was newline? Skip filling the whole next line with empty
{
newLine = false;
continue;
}
}
// If we are newlining we need to fill the remaining with blanks
if (newLine)
{
newLine = false;
for (int i2 = col; i2 <= _width; i2++)
{
_tmpBuffer.Add(new CharInfo(' ', _defaultColor));
}
col = 0;
row++;
continue;
}
if (i >= text.Length)
break;
// Add character
_tmpBuffer.Add(new CharInfo(text[i], _defaultColor));
}
var cursorI = (_cursorTop * _width) + _cursorLeft;
// Get our end position
var end = cursorI + _tmpBuffer.Count;
// If we are overflowing (scrolling) then we need to complete our last line with spaces (align buffer with line ending)
if (end > _buffer.Length && col != 0)
{
for (int i = col; i <= _width; i++)
{
_tmpBuffer.Add(new CharInfo(' ', _defaultColor));
}
col = 0;
row++;
}
// Chop start of buffer to fit into destination buffer
if (_tmpBuffer.Count > _buffer.Length)
_tmpBuffer.RemoveRange(0, _tmpBuffer.Count - _buffer.Length);
// Convert to array so we can batch copy
var tmpArray = _tmpBuffer.ToArray();
// Are we going to write outside of buffer?
end = cursorI + _tmpBuffer.Count;
var scrollUp = 0;
if (end > _buffer.Length)
{
scrollUp = end - _buffer.Length;
}
// Scroll up
if (scrollUp > 0)
{
Array.Copy(_buffer, scrollUp, _buffer, 0, _buffer.Length - scrollUp);
cursorI -= scrollUp;
}
var lastPos = Math.Min(_buffer.Length, cursorI + tmpArray.Length);
var firstPos = lastPos - tmpArray.Length;
// Copy new data in
Array.Copy(tmpArray, 0, _buffer, firstPos, tmpArray.Length);
// Set new cursor position
_cursorLeft = col;
_cursorTop = Math.Min(_height, _cursorTop + row + 1);
// Write to main buffer
if (AutoDraw)
Draw();
}
#endregion
#region Input
private string _currentInputBuffer = "";
private string _inputPrompt;
private int _inputCursorPos = 0;
private int _inputFrameStart = 0;
// Not used because COMMON_LVB_UNDERSCORE doesn't work
//private bool _inputCursorState = false;
//private int _inputCursorStateChange = 0;
private int _cursorBlinkLeft = 0;
private int _cursorBlinkTop = 0;
public string InputPrompt
{
get { return _inputPrompt; }
set
{
_inputPrompt = value;
ResetInput();
}
}
private void ResetInput()
{
SetCursorPosition(0, 0);
_inputCursorPos = Math.Min(_currentInputBuffer.Length, _inputCursorPos);
var inputPrompt = InputPrompt + "[" + _currentInputBuffer.Length + "] ";
// What is the max length we can write?
var maxLen = _width - inputPrompt.Length;
if (maxLen < 0)
return;
if (_inputCursorPos > _inputFrameStart + maxLen)
_inputFrameStart = _inputCursorPos - maxLen;
if (_inputCursorPos < _inputFrameStart)
_inputFrameStart = _inputCursorPos;
_cursorBlinkLeft = inputPrompt.Length + _inputCursorPos - _inputFrameStart;
//if (_currentInputBuffer.Length - _inputFrameStart < maxLen)
// _inputFrameStart--;
// Write and pad the end
var str = inputPrompt + _currentInputBuffer.Substring(_inputFrameStart, Math.Min(_currentInputBuffer.Length - _inputFrameStart, maxLen));
var spaceLen = _width - str.Length;
Write(str + (spaceLen > 0 ? new String(' ', spaceLen) : ""));
UpdateCursorBlink(true);
}
private void UpdateCursorBlink(bool force)
{
// Since COMMON_LVB_UNDERSCORE doesn't work we won't be controlling blink
//// Blink the cursor
//if (Environment.TickCount > _inputCursorStateChange)
//{
// _inputCursorStateChange = Environment.TickCount + 250;
// _inputCursorState = !_inputCursorState;
// force = true;
//}
//if (force)
// SetCursorBlink(_cursorBlinkLeft, _cursorBlinkTop, _inputCursorState);
SetCursorBlink(_left + _cursorBlinkLeft, _top + _cursorBlinkTop, true);
}
public string ReadLine()
{
Console.CursorVisible = false;
Clear();
ResetInput();
while (true)
{
Thread.Sleep(50);
while (Console.KeyAvailable)
{
var key = Console.ReadKey(true);
switch (key.Key)
{
case ConsoleKey.Enter:
{
var ret = _currentInputBuffer;
_inputCursorPos = 0;
_currentInputBuffer = "";
return ret;
break;
}
case ConsoleKey.LeftArrow:
{
_inputCursorPos = Math.Max(0, _inputCursorPos - 1);
break;
}
case ConsoleKey.RightArrow:
{
_inputCursorPos = Math.Min(_currentInputBuffer.Length, _inputCursorPos + 1);
break;
}
case ConsoleKey.Backspace:
{
if (_inputCursorPos > 0)
{
_inputCursorPos--;
_currentInputBuffer = _currentInputBuffer.Remove(_inputCursorPos, 1);
}
break;
}
case ConsoleKey.Delete:
{
if (_inputCursorPos < _currentInputBuffer.Length - 1)
_currentInputBuffer = _currentInputBuffer.Remove(_inputCursorPos, 1);
break;
}
default:
{
var pos = _inputCursorPos;
//if (_inputCursorPos == _currentInputBuffer.Length)
_inputCursorPos++;
_currentInputBuffer = _currentInputBuffer.Insert(pos, key.KeyChar.ToString());
break;
}
}
ResetInput();
}
// COMMON_LVB_UNDERSCORE doesn't work so we use Consoles default cursor
//UpdateCursorBlink(false);
}
}
#endregion
}