Question

我正在编写一个小实用程序库，以帮助提高写入控制台时的性能，而且我遇到的问题是它无法实际输出任何文本。以下是我的代码：

public static class QuickDraw
{
    private static short Width => (short)Console.WindowWidth;
    private static short Height => (short)Console.WindowHeight;

    private static SafeFileHandle Handle =>
        Kernel32.CreateFile("$CONOUT", 0x40000000, 2, IntPtr.Zero, FileMode.Open, 0, IntPtr.Zero);

    private static Kernel32.Coord Cursor =>
        new Kernel32.Coord((short)Console.CursorLeft, (short)Console.CursorTop);

    private static Kernel32.SmallRect WriteRegion =>
        new Kernel32.SmallRect() { Left = 0, Top = 0, Right = Width, Bottom = Height };
    private static Kernel32.Coord BufferSize =>
        new Kernel32.Coord(Width, Height);
    private static Kernel32.Coord BufferCoord =>
        new Kernel32.Coord(0, 0);

    public static void Write(char[] text, ConsoleColor fg, ConsoleColor bg)
    {
        Kernel32.CharInfo[] buffer = new Kernel32.CharInfo[Width * Height];
        Kernel32.Coord cursor = Cursor;

        for (int i = 0; i < text.Length; i++)
        {
            if (text[i] == '\n')
            {
                cursor.X = 0;
                cursor.Y++;
            }
            else
            {
                int index = (cursor.Y * Width) + cursor.X;

                // Set character
                buffer[index].Char.AsciiChar = (byte)text[i];

                // Set color
                // (Crazy heckin bitwise crap, don't touch.)
                buffer[index].Attributes = (short)((int)fg | ((int)bg | (2 << 4)));

                // Increment cursor
                cursor.X++;
            }

            // Make sure that cursor does not exceed bounds of window
            if (cursor.X >= Width)
            {
                cursor.X = 0;
                cursor.Y++;
            }
            if (cursor.Y >= Height)
            {
                cursor.Y = 0;
            }
        }

        var writeRegion = WriteRegion;
        Kernel32.WriteConsoleOutput(Handle, buffer, BufferSize, BufferCoord, ref writeRegion);

        Console.SetCursorPosition(cursor.X, cursor.Y);
    }
}

// Taken from https://stackoverflow.com/a/2754674/7937949
internal static class Kernel32
{
    [DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
    public 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)]
    public static extern bool WriteConsoleOutput(
        SafeFileHandle hConsoleOutput,
        CharInfo[] lpBuffer,
        Coord dwBufferSize,
        Coord dwBufferCoord,
        ref SmallRect lpWriteRegion);

    [StructLayout(LayoutKind.Sequential)]
    public struct Coord
    {
        public short X;
        public short Y;

        public Coord(short x, short y)
        {
            X = x;
            Y = y;
        }
    }

    [StructLayout(LayoutKind.Explicit)]
    public struct CharUnion
    {
        [FieldOffset(0)] public char UnicodeChar;
        [FieldOffset(0)] public byte AsciiChar;
    }

    [StructLayout(LayoutKind.Explicit)]
    public struct CharInfo
    {
        [FieldOffset(2)] public CharUnion Char;
        [FieldOffset(2)] public short Attributes;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct SmallRect
    {
        public short Left;
        public short Top;
        public short Right;
        public short Bottom;
    }
}

我主要从this post开始实施，添加了一个新类来简化其使用。我不完全确定我的问题在哪里，因为我的调试器工作不正常，但我很确定它是在QuickDraw的实现中。

当我尝试使用QuickDraw.Write()时，光标移动到它试图打印的任何字符串的末尾，但实际上没有显示任何字符串。我做错了什么？

Answer 1

首先，您没有正确复制代码。有一些错误。

更改

[FieldOffset(2)] public CharUnion Char;

到

[FieldOffset(0)] public CharUnion Char;
将$CONOUT更改为此CONOUT$
首先设置属性，然后设置AsciiChar

当然，如果您想要正确的前景色/背景色表示，则必须删除2 << 4。我甚至不知道你为什么把它放在那里。

来自Kernel32的WriteConsoleOutput（）不显示文本

1 个答案: