Как создать каретку свой собственной формы?

{ 
  The example below demonstrates creating custom caret: 
} 
 
unit Unit1; 
 
interface 
 
uses 
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, 
  ExtCtrls, StdCtrls; 
 
type 
  TForm1 = class(TForm) 
    Memo1: TMemo; 
    Image1: TImage; 
    Edit1: TEdit; 
    procedure Memo1MouseDown(Sender: TObject; Button: TMouseButton; 
      Shift: TShiftState; X, Y: Integer); 
    procedure Edit1MouseDown(Sender: TObject; Button: TMouseButton; 
      Shift: TShiftState; X, Y: Integer); 
  private 
    { Private declarations } 
  public 
    { Public declarations } 
  end; 
 
var 
  Form1: TForm1; 
 
implementation 
 
{$R *.DFM} 
 
procedure TForm1.Memo1MouseDown(Sender: TObject; Button: TMouseButton; 
  Shift: TShiftState; X, Y: Integer); 
begin 
  CreateCaret(Memo1.Handle, Image1.Picture.Bitmap.Handle, 0, 0); 
  ShowCaret(Memo1.Handle); 
end; 
 
procedure TForm1.Edit1MouseDown(Sender: TObject; Button: TMouseButton; 
  Shift: TShiftState; X, Y: Integer); 
begin 
  CreateCaret(Edit1.Handle, 0, 10, 4); 
  ShowCaret(Edit1.Handle); 
end; 
 
end. 
 
 
{The form file source (*.dfm) } 
 
object Form1: TForm1 
  Left = 192 
  Top = 107 
  Width = 544 
  Height = 375 
  Caption = 'Form1' 
  Color = clBtnFace 
  Font.Charset = DEFAULT_CHARSET 
  Font.Color = clWindowText 
  Font.Height = -11 
  Font.Name = 'MS Sans Serif' 
  Font.Style = [] 
  OldCreateOrder = False 
  PixelsPerInch = 96 
  TextHeight = 13 
  object Image1: TImage 
    Left = 12 
    Top = 4 
    Width = 16 
    Height = 16 
    AutoSize = True 
    Picture.Data = { 
      07544269746D6170B6020000424DB602000000000000B6000000280000001000 
      0000100000000100100000000000000200000000000000000000100000000000 
      000000000000000080000080000000808000800000008000800080800000C0C0 
      C000808080000000FF0000FF000000FFFF00FF000000FF00FF00FFFF0000FFFF 
      FF00000000000000000000000000000000000000000000000000000000000000 
      0000000000000000000000000000000000000000000000000000000000000000 
      000000000000FF7FFF7FFF7FFF7F000000000000FF7FFF7FFF7FFF7FFF7FFF7F 
      00000000FF7FFF7FFF7FFF7F000000000000FF7FFF7FFF7FFF7FFF7FFF7F0000 
      0000FF7FFF7FFF7FFF7FFF7F00000000FF7FFF7FFF7FFF7FFF7FFF7FFF7F0000 
      000000000000FF7FFF7FFF7F0000000000000000FF7FFF7FFF7FFF7F00000000 
      0000000000000000FF7FFF7FFF7FFF7FFF7FFF7FFF7FFF7FFF7FFF7F00000000 
      0000000000000000FF7FFF7FFF7FFF7FFF7FFF7FFF7FFF7FFF7F000000000000 
      0000000000000000FF7FFF7FFF7F00000000FF7FFF7FFF7FFF7F000000000000 
      00000000000000000000FF7FFF7FFF7FFF7FFF7FFF7FFF7F0000000000000000 
      00000000000000000000FF7FFF7FFF7FFF7FFF7FFF7FFF7F0000000000000000 
      000000000000000000000000FF7FFF7FFF7FFF7FFF7FFF7F0000000000000000 
      000000000000000000000000FF7FFF7FFF7FFF7FFF7F00000000000000000000 
      0000000000000000000000000000FF7FFF7FFF7FFF7F00000000000000000000 
      0000000000000000000000000000FF7FFF7FFF7F000000000000000000000000 
      00000000000000000000000000000000FF7F0000000000000000000000000000 
      0000} 
  end 
  object Memo1: TMemo 
    Left = 12 
    Top = 36 
    Width = 149 
    Height = 149 
    Lines.Strings = ('Memo1') 
    TabOrder = 0 
    OnMouseDown = Memo1MouseDown 
  end 
  object Edit1: TEdit 
    Left = 220 
    Top = 60 
    Width = 121 
    Height = 21 
    TabOrder = 1 
    Text = 'Edit1' 
    OnMouseDown = Edit1MouseDown 
  end 
end 

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