VCL 中的 Windows API 函数: BeginPath、EndPath

BeginPath         {路径开始} EndPath {路径结束}
StrokePath        {绘制路径}
FillPath          {填充路径}
StrokeAndFillPath {绘制并填充路径}

//在路径中可以使用的图形命令有:
AngleArc
Arc
ArcTo
Chord
CloseFigure
Ellipse
ExtTextOut
LineTo
MoveToEx
Pie
PolyBezier
PolyBezierTo
PolyDraw
Polygon
Polyline
PolylineTo
PolyPolygon
PolyPolyline
Rectangle
RoundRect
TextOut

---

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 FormPaint(Sender: TObject);
    procedure RadioGroup1Click(Sender: TObject);
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.FormCreate(Sender: TObject);
begin
  RadioGroup1.Items.CommaText := '绘制路径,填充路径,绘制并填充';
  RadioGroup1.ItemIndex := 0;
  RadioGroup1.Columns := RadioGroup1.Items.Count;
end;

procedure TForm1.FormPaint(Sender: TObject);
begin
  Canvas.Font.Size := 36;
  Canvas.Font.Style := [fsBold];
  SetBkMode(Canvas.Handle, TRANSPARENT);

  BeginPath(Canvas.Handle);
  Canvas.Rectangle(10,10,110,110);
  Canvas.TextOut(20,30,'Delphi 2007');
  EndPath(Canvas.Handle);

  Canvas.Brush.Color := clYellow;
  Canvas.Pen.Color := clRed;

  case RadioGroup1.ItemIndex of
    0: StrokePath(Canvas.Handle);
    1: FillPath(Canvas.Handle);
    2: StrokeAndFillPath(Canvas.Handle);
  end;
end;

procedure TForm1.RadioGroup1Click(Sender: TObject);
begin
  Repaint;
end;

end.

窗体设计:

---

object Form1: TForm1
  Left = 373
  Top = 260
  Caption = 'Form1'
  ClientHeight = 193
  ClientWidth = 321
  Color = clBtnFace
  Font.Charset = DEFAULT_CHARSET
  Font.Color = clWindowText
  Font.Height = -11
  Font.Name = 'Tahoma'
  Font.Style = []
  OldCreateOrder = False
  Position = poDesigned
  OnCreate = FormCreate
  OnPaint = FormPaint
  PixelsPerInch = 96
  TextHeight = 13
  object RadioGroup1: TRadioGroup
    Left = 28
    Top = 131
    Width = 265
    Height = 49
    Caption = 'RadioGroup1'
    TabOrder = 0
    OnClick = RadioGroup1Click
  end
end