public static IEnumerable <string> ReadFromBuffer(short x, short y, short width, short height)
{
IntPtr buffer = Marshal.AllocHGlobal(width * height * Marshal.SizeOf(typeof(CHAR_INFO)));
if (buffer == null)
{
throw new OutOfMemoryException();
}
try
{
var coord = new Coord();
var rc = new SmallRect
{
Left = x,
Top = y,
Right = (short)(x + width - 1),
Bottom = (short)(y + height - 1)
};
var size = new Coord {
X = width, Y = height
};
const int STD_OUTPUT_HANDLE = -11;
if (!ReadConsoleOutput(GetStdHandle(STD_OUTPUT_HANDLE), buffer, size, coord, ref rc))
{
// 'Not enough storage is available to process this command' may be raised for buffer size > 64K (see ReadConsoleOutput doc.)
throw new Win32Exception(Marshal.GetLastWin32Error());
}
IntPtr ptr = buffer;
for (int h = 0; h < height; h++)
{
var sb = new StringBuilder();
for (int w = 0; w < width; w++)
{
var ci = (CHAR_INFO)Marshal.PtrToStructure(ptr, typeof(CHAR_INFO));
char[] chars = Console.OutputEncoding.GetChars(ci.charData);
sb.Append(chars[0]);
ptr += Marshal.SizeOf(typeof(CHAR_INFO));
}
yield return(sb.ToString());
}
}
finally
{
Marshal.FreeHGlobal(buffer);
}
}
private static extern bool ReadConsoleOutput(IntPtr hConsoleOutput, IntPtr lpBuffer, Coord dwBufferSize, Coord dwBufferCoord, ref SmallRect lpReadRegion);
