引言: 切換 Form 的時候, 移動 Form 的時候, click 的時候

  procedure TForm1.StringGrid1DrawCell(Sender: TObject; ACol, ARow: Integer;
  Rect: TRect; State: TGridDrawState);
begin
    if ToolButton2.Down then
      showmessage('Hello!');
    if gdSelected in State then
    begin
     StringGrid1.Canvas.Font.Style := [fsBold];
     StringGrid1.Canvas.Font.Color:=clRed;
     StringGrid1.Canvas.FillRect(Rect);
     DrawText(StringGrid1.Canvas.Handle,
       pChar(StringGrid1.Cells[ACol,ARow]),
       Length(StringGrid1.Cells[ACol,ARow]),
       Rect, 
       DT_RIGHT or 
       DT_SINGLELINE or 
       DT_VCENTER) 
     end;
    end; 

procedure TForm1.StringAlignGrid1SelectCell(Sender: TObject; ACol,
  ARow: Integer; var CanSelect: Boolean);
var x,y: integer;
begin
  // 恢復字型初始值
  for x := 0 to StringAlignGrid1.ColCount -1 do begin
    for y := 0 to StringAlignGrid1.RowCount -1 do begin
      StringAlignGrid1.CellFont[x, y].Style := [];
      StringAlignGrid1.CellFont[x, y].Color := clBlack;
    end;
  end;      // 改變字型
  StringAlignGrid1.CellFont[ACol, ARow].Style := [fsBold];
  StringAlignGrid1.CellFont[ACol, ARow].Color := clRed;
end;

 
procedure TForm1.ToolButton1Click(Sender: TObject);
var
  SelectRect:TGridRect;
  DisplayRect:TRect;
  x, y: Integer;
  TextAlign: word;
begin
 SelectedRect:=StringAlignGrid1.Selection;
 for  x:=SelectedRect.Left to SelectedRect.Right do
    begin
     for y:= SelectedRect.top to SelectedRect.Bottom do
      begin
       Canvas.Font.Style := [fsBold];
       Canvas.Font.Color:=clRed;
       DisplayRect:=Rect(SelectedRect.left ,SelectedRect.top,
                       SelectedRect.right,SelectedRect.bottom);//語句1
       Canvas.FillRect(DisplayRect);
       TextAlign:= DT_LEFT or DT_SINGLELINE OR DT_VCENTER;
       DrawText(StringAlignGrid1.Canvas.Handle,
       pChar(StringAlignGrid1.Cells[x,y]),
       Length(StringAlignGrid1.Cells[x,y]),
       DisplayRect,  //語句2
       TextAlign); 
       end;
    end;
end; 

var
  SelectedRect:TGridRect;
  DisplayRect:TRect;
  x, y: Integer;
begin
  SelectedRect:=StringAlignGrid1.Selection;
  for  x:=SelectedRect.Left to SelectedRect.Right do
  begin
    for y:= SelectedRect.top to SelectedRect.Bottom do
    begin
      StringAlignGrid1.CellFont[x, y].Style := [fsBold];
      StringAlignGrid1.CellFont[x, y].Color := clRed;
    end;
  end;
end;

function TForm1.CurrRect:TGridRect;//表示被选择的区域
begin
  Result:=stringAlignGrid1.Selection;
end;
  
procedure TForm1.ChangeFontStyle   (Toolbtn:TToolButton;Style:TFontStyle);
var
 x,y:integer;
begin
   for x :=CurrRect.Left to CurrRect.Right do
    for y := CurrRect.top to CurrRect.Bottom do
     begin
       with  StringAlignGrid1 do
        begin
         if Toolbtn.Down then
            CellFont[x, y].Style :=CellFont[x, y].Style [Style]
         else
            CellFont[x, y].Style :=CellFont[x, y].Style-[Style];
        end;
     end;
end;
  
procedure TForm1.ToolButton1Click(Sender: TObject);
begin
  ChangeFontStyle(ToolButton1,fsBold); // 或fsItalic等
end;    procedure TForm1.AlignFontStyle(ToolBtn:TToolButton;AlignStle:TMyAlign);
var
 x,y:integer;
begin
   for x :=CurrRect.Left to CurrRect.Right do
   for y := CurrRect.top to CurrRect.Bottom do
    if Toolbtn.down then
     StringAlignGrid1.AlignCell[x, y]:=AlignStle;
end;    procedure TForm1.ToolButton2Click(Sender: TObject);
begin
 AlignFontStyle(ToolButton2,alcenter);//或alright,alleft
end;