...Text in einem TMemo hervorheben?
Autor: Gon Perez-Jimenez
(**
* Highlight with TMemo Impossible? try this...
* by Gon Perez-Jimenez May'04
*
* This is a sample how to work with highlighting within TMemo component by
* using interjected class technique.
*
* Of course, this code is still uncompleted but it works fine for my
* purposes, so, hope you can improve it and use it.
*
* Drop onto your TForm (Form1), a TMemo (Memo1), a TLabel (Label1)
* and a TListBox (KeywordList)
*
* Insert in the TListBox Items some Pascal keywords in lowercase !!!
*
* That's all! Enjoy
*)
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
StdCtrls, ComCtrls;
type
// Interjected Class
TMemo = class(stdctrls.TMemo)
private
procedure WMPaint(var Message: TWMPaint); message WM_PAINT;
procedure WMSize(var Message: TWMSize); message WM_SIZE;
procedure WMMove(var Message: TWMMove); message WM_MOVE;
procedure WMVScroll(var Message: TWMMove); message WM_VSCROLL;
procedure WMMousewheel(var Message: TWMMove); message WM_MOUSEWHEEL;
protected
procedure Change; override;
procedure KeyDown(var Key: Word; Shift: TShiftState); override;
procedure KeyUp(var Key: Word; Shift: TShiftState); override;
procedure MouseDown(Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
override;
procedure MouseUp(Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
override;
public
PosLabel: TLabel;
procedure Update_label;
procedure GotoXY(mCol, mLine: Integer);
function Line: Integer;
function Col: Integer;
function TopLine: Integer;
function VisibleLines: Integer;
end;
TForm1 = class(TForm)
Memo1: TMemo;
Label1: TLabel;
KeywordList: TListBox;
procedure FormCreate(Sender: TObject);
procedure Memo1KeyUp(Sender: TObject; var Key: Word;
Shift: TShiftState);
procedure FormClose(Sender: TObject; var Action: TCloseAction);
private
{ Private declarations }
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.DFM}
////////////////////////////////////////////////////////////////////////////////
// functions for managing keywords and numbers of each line of TMemo ///////////
////////////////////////////////////////////////////////////////////////////////
function IsSeparator(Car: Char): Boolean;
begin
case Car of
'.', ';', ',', ':', '¡', '!', '·', '"', '''', '^', '+', '-', '*', '/', '\', '¨', ' ',
'`', '[', ']', '(', ')', 'º', 'ª', '{', '}', '?', '¿', '%', '=': Result := True;
else
Result := False;
end;
end;
////////////////////////////////////////////////////////////////////////////////
function NextWord(var s: string; var PrevWord: string): string;
begin
Result := '';
PrevWord := '';
if s = '' then Exit;
while (s <> '') and IsSeparator(s[1]) do
begin
PrevWord := PrevWord + s[1];
Delete(s, 1,1);
end;
while (s <> '') and not IsSeparator(s[1]) do
begin
Result := Result + s[1];
Delete(s, 1,1);
end;
end;
////////////////////////////////////////////////////////////////////////////////
function IsKeyWord(s: string): Boolean;
begin
Result := False;
if s = '' then Exit;
Result := Form1.KeywordList.Items.IndexOf(lowercase(s)) <> -1;
end;
////////////////////////////////////////////////////////////////////////////////
function IsNumber(s: string): Boolean;
var
i: Integer;
begin
Result := False;
for i := 1 to Length(s) do
case s[i] of
'0'..'9':;
else
Exit;
end;
Result := True;
end;
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
// New or overrided methods and properties for TMemo using Interjected Class ///
// Technique ///////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
function TMemo.VisibleLines: Integer;
begin
Result := Height div (Abs(Self.Font.Height) + 2);
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.GotoXY(mCol, mLine: Integer);
begin
Dec(mLine);
SelStart := 0;
SelLength := 0;
SelStart := mCol + Self.Perform(EM_LINEINDEX, mLine, 0);
SelLength := 0;
SetFocus;
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.Update_label;
begin
if PosLabel = nil then Exit;
PosLabel.Caption := '(' + IntToStr(Line + 1) + ',' + IntToStr(Col) + ')';
end;
////////////////////////////////////////////////////////////////////////////////
function TMemo.TopLine: Integer;
begin
Result := SendMessage(Self.Handle, EM_GETFIRSTVISIBLELINE, 0, 0);
end;
////////////////////////////////////////////////////////////////////////////////
function TMemo.Line: Integer;
begin
Result := SendMessage(Self.Handle, EM_LINEFROMCHAR, Self.SelStart, 0);
end;
////////////////////////////////////////////////////////////////////////////////
function TMemo.Col: Integer;
begin
Result := Self.SelStart - SendMessage(Self.Handle, EM_LINEINDEX,
SendMessage(Self.Handle,
EM_LINEFROMCHAR, Self.SelStart, 0), 0);
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.WMVScroll(var Message: TWMMove);
begin
Update_label;
Invalidate;
inherited;
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.WMSize(var Message: TWMSize);
begin
Invalidate;
inherited;
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.WMMove(var Message: TWMMove);
begin
Invalidate;
inherited;
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.WMMousewheel(var Message: TWMMove);
begin
Invalidate;
inherited;
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.Change;
begin
Update_label;
Invalidate;
inherited Change;
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.KeyDown(var Key: Word; Shift: TShiftState);
begin
Update_label;
inherited KeyDown(Key, Shift);
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.KeyUp(var Key: Word; Shift: TShiftState);
begin
Update_label;
inherited KeyUp(Key, Shift);
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.MouseDown(Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
Update_label;
inherited MouseDown(Button, Shift, X, Y);
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.MouseUp(Button: TMouseButton; Shift: TShiftState; X, Y: Integer);
begin
Update_label;
inherited MouseUp(Button, Shift, X, Y);
end;
////////////////////////////////////////////////////////////////////////////////
procedure TMemo.WMPaint(var Message: TWMPaint);
var
PS: TPaintStruct;
DC: HDC;
Canvas: TCanvas;
i: Integer;
X, Y: Integer;
OldColor: TColor;
Size: TSize;
Max: Integer;
s, Palabra, PrevWord: string;
begin
DC := Message.DC;
if DC = 0 then DC := BeginPaint(Handle, PS);
Canvas := TCanvas.Create;
try
OldColor := Font.Color;
Canvas.Handle := DC;
Canvas.Font.Name := Font.Name;
Canvas.Font.Size := Font.Size;
with Canvas do
begin
Max := TopLine + VisibleLines;
if Max > Pred(Lines.Count) then Max := Pred(Lines.Count);
//Limpio la sección visible
Brush.Color := Self.Color;
FillRect(Self.ClientRect);
Y := 1;
for i := TopLine to Max do
begin
X := 2;
s := Lines[i];
//Detecto todas las palabras de esta línea
Palabra := NextWord(s, PrevWord);
while Palabra <> '' do
begin
Font.Color := OldColor;
TextOut(X, Y, PrevWord);
GetTextExtentPoint32(DC, PChar(PrevWord), Length(PrevWord), Size);
Inc(X, Size.cx);
Font.Color := clBlack;
if IsKeyWord(Palabra) then
begin
Font.Color := clHighlight;
TextOut(X, Y, Palabra);
{
//Draw dot underline
Pen.Color := clHighlight;
Pen.Style := psDot;
PolyLine([ Point(X,Y+13), Point(X+TextWidth(Palabra),Y+13)]);
}
end
else if IsNumber(Palabra) then
begin
Font.Color := $000000DD;
TextOut(X, Y, Palabra);
end
else
TextOut(X, Y, Palabra);
GetTextExtentPoint32(DC, PChar(Palabra), Length(Palabra), Size);
Inc(X, Size.cx);
Palabra := NextWord(s, PrevWord);
if (s = '') and (PrevWord <> '') then
begin
Font.Color := OldColor;
TextOut(X, Y, PrevWord);
end;
end;
if (s = '') and (PrevWord <> '') then
begin
Font.Color := OldColor;
TextOut(X, Y, PrevWord);
end;
s := 'W';
GetTextExtentPoint32(DC, PChar(s), Length(s), Size);
Inc(Y, Size.cy);
end;
end;
finally
if Message.DC = 0 then EndPaint(Handle, PS);
end;
Canvas.Free;
inherited;
end;
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
// Procedures for Form1 ////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////
procedure TForm1.FormCreate(Sender: TObject);
begin
Memo1.PosLabel := Label1;
Memo1.Update_label;
end;
////////////////////////////////////////////////////////////////////////////////
procedure TForm1.Memo1KeyUp(Sender: TObject; var Key: Word;
Shift: TShiftState);
begin
if Key = VK_F1 then Memo1.Invalidate;
end;
////////////////////////////////////////////////////////////////////////////////
procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
Action := caFree;
end;
////////////////////////////////////////////////////////////////////////////////
end.
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