Memory Mapped Files y RichEdit

Aquí tienes una utilidad que puede que te sea de ayuda.
Saludos,
Antipauli
unit CR_UORichEdit;
{ Enhanced TRichEdit support for DelphiDrop by UnitOOPS SOftware.
Last Modified: 05/04/99
}
interface
uses
Windows, Messages, Controls, Classes, ComCtrls;
type
// A TRichEdit descendant that exposes a published RTF property, to support DFM
// persistence for the RTF in a TRichEdit. This also allows you to make changes
// that recreate the window handle (e.g., changing the scrollbar settings at
// design time) and retain the rich text, even if the control's contents are
// modified at run-time.
TUORichEdit = class(TRichEdit)
private
FRTF: string;
procedure UpdateRTF;
procedure SetRTF(const aRTF: string);
protected
procedure CMRecreateWnd(var Message: TMessage); message CM_RECREATEWND;
published
property RTF: string read FRTF write SetRTF;
end;
// Helper functions that do the actual RTF manipulations.
procedure AddContentToRichEdit(aRTFString: string; aRichEdit: TCustomRichEdit;
isRTF: boolean; insert: boolean);
function GetContentFromRichEdit(aRichEdit: TCustomRichEdit; asRTF: boolean;
selectionOnly: boolean): string;
implementation
uses
SysUtils, RichEdit;
procedure TUORichEdit.UpdateRTF;
// Update the RTF from the private FRTF
begin
// Clear out the rich edit
Lines.Clear;
// Use the helper function to add the content.
AddContentToRichEdit(FRTF, Self, true, true);
end;
procedure TUORichEdit.SetRTF(const aRTF: string);
// Property setter for RTF. Only update things if changed.
begin
if (AnsiCompareStr(aRTF, FRTF) <> 0) then
begin
FRTF := aRTF;
UpdateRTF;
end;
end;
procedure TUORichEdit.CMRecreateWnd(var Message: TMessage);
// This is the main raison d'etre for the TUORichEdit. Without this, every time
// the window handle is destroyed, the rich text is lost, and only the plain
// text remains. We catch the notification of window recreation, do the inherited
// stuff (actually allow it to be recreated), then put the RTF back in.
begin
// We have a handle - pull the RTF out of the control, as it may have been changed
// by the user. We store it temporarily so it can survive handle recreation,
// then add it back.
if (WindowHandle <> 0) then
begin
FRTF := GetContentFromRichEdit(Self, true, false);
end;
// If there's no handle, we're being created for the first time,
// so we'll add the RTF already stored in the RTF property.
// Do the handle recreation
inherited;
// Now put the RTF back.
UpdateRTF;
end;
function EMStreamInCallback(dwCookie: Longint; pbBuff: PByte;
cb: Longint; var pcb: Longint): Longint; stdcall;
// Callback function for EM_STREAMIN handling.
// This code, and the following "AddRTFToRichEdit" procedure based on corrected
// versions of code examples by Ralph Friedman (TeamB).
var
theStream: TStringStream;
begin
// dwCookie is Application-defined, so we're passing the stream containing
// the formatted text to be added.
theStream := TStringStream(dwCookie);
result := 0;
with theStream do
begin
// Deal with the precise case where we get to the end of the buffer.
// Happens for very small buffers (probably never for RTF due to all of the
// junk that surrounds the smallest piece of RTF), but definitely for text!
// This case was missing from the original code.
if (Size = position) then
begin
pcb := 0;
exit;
end;
if (Size - Position) <= cb then
begin
pcb := Size;
Read(pbBuff^, Size);
end
else
begin
pcb := cb;
Read(pbBuff^, cb);
end;
end;
end;
procedure AddContentToRichEdit(aRTFString: string; aRichEdit: TCustomRichEdit;
isRTF: boolean; insert: boolean);
// This code, and the preceding "EMS