public class ConsoleReader
{
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
{
COORD coord = new COORD( );
SMALL_RECT rc = new SMALL_RECT( );
rc.Left = x;
rc.Top = y;
rc.Right = (short) ( x + width - 1 );
rc.Bottom = (short) ( y + height - 1 );
COORD size = new COORD( );
size.X = width;
size.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++ )
{
StringBuilder sb = new StringBuilder( );
for ( int w = 0; w < width; w++ )
{
CHAR_INFO 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 );
}
}
[StructLayout( LayoutKind.Sequential )]
private struct CHAR_INFO
{
[MarshalAs( UnmanagedType.ByValArray, SizeConst = 2 )]
public byte[] charData;
public short attributes;
}
[StructLayout( LayoutKind.Sequential )]
private struct COORD
{
public short X;
public short Y;
}
[StructLayout( LayoutKind.Sequential )]
private struct SMALL_RECT
{
public short Left;
public short Top;
public short Right;
public short Bottom;
}
[StructLayout( LayoutKind.Sequential )]
private struct CONSOLE_SCREEN_BUFFER_INFO
{
public COORD dwSize;
public COORD dwCursorPosition;
public short wAttributes;
public SMALL_RECT srWindow;
public COORD dwMaximumWindowSize;
}
[DllImport( "kernel32.dll", SetLastError = true )]
private static extern bool ReadConsoleOutput( IntPtr hConsoleOutput, IntPtr lpBuffer, COORD dwBufferSize, COORD dwBufferCoord, ref SMALL_RECT lpReadRegion );
[DllImport( "kernel32.dll", SetLastError = true )]
private static extern IntPtr GetStdHandle( int nStdHandle );
}

C# read cmd console