WinAPI: 输入光标相关的函数[3]

本例测试修改光标的形色, 效果图:

---

代码文件:

---

unit Unit1;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls;

type
  TForm1 = class(TForm)
    RadioGroup1: TRadioGroup;
    procedure FormCreate(Sender: TObject);
    procedure FormMouseUp(Sender: TObject; Button: TMouseButton;
      Shift: TShiftState; X, Y: Integer);
    procedure RadioGroup1Click(Sender: TObject);
    procedure FormDestroy(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

var
  bit: TBitmap;

procedure TForm1.FormCreate(Sender: TObject);
const
  c = '★';
begin
  RadioGroup1.Caption := '光标形色';
  RadioGroup1.Items.CommaText := '黑色,灰度,自定义';
  RadioGroup1.ItemIndex := 0;

  bit := TBitmap.Create;
  bit.Canvas.Font.Size := 16;
  bit.Width := bit.Canvas.TextWidth(c);
  bit.Height := bit.Canvas.TextHeight(c);
  bit.Canvas.TextOut(0, 0, c);
end;

procedure TForm1.FormDestroy(Sender: TObject);
begin
  SetCaretBlinkTime(530);
  bit.Free;
end;

procedure TForm1.FormMouseUp(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
var
  h: HBITMAP;
begin
  DestroyCaret;

  h := 0;
  case RadioGroup1.ItemIndex of
    1: h := 1;
    2: h := bit.Handle;
  end;
  CreateCaret(Handle, h, 4, 32);
  SetCaretPos(X,Y);
  ShowCaret(Handle);
end;

procedure TForm1.RadioGroup1Click(Sender: TObject);
var
  h: HBITMAP;
  pt: TPoint;
begin
  GetCaretPos(pt);
  DestroyCaret;

  h := 0;
  case RadioGroup1.ItemIndex of
    1: h := 1;
    2: h := bit.Handle;
  end;
  CreateCaret(Handle, h, 4, 32);
  SetCaretPos(pt.X, pt.Y);
  ShowCaret(Handle);
end;

end.

窗体文件:

---

object Form1: TForm1
  Left = 0
  Top = 0
  Caption = 'Form1'
  ClientHeight = 137
  ClientWidth = 228
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'Tahoma'
  Font.Style = []
  OldCreateOrder = False
  OnCreate = FormCreate
  OnDestroy = FormDestroy
  OnMouseUp = FormMouseUp
  PixelsPerInch = 96
  TextHeight = 13
  object RadioGroup1: TRadioGroup
    Left = 137
    Top = 16
    Width = 80
    Height = 113
    Caption = 'RadioGroup1'
    TabOrder = 0
    OnClick = RadioGroup1Click
  end
end