再學 GDI+[27]: TGPPen – 畫筆樣式 – SetDashStyle

本例:

代碼檔案:

unit Unit1;interfaceuses  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,  Dialogs, StdCtrls, ExtCtrls;type  TForm1 = class(TForm)    ComboBox1: TComboBox;    procedure FormCreate(Sender: TObject);    procedure FormPaint(Sender: TObject);    procedure ComboBox1Change(Sender: TObject);  end;var  Form1: TForm1;implementation{$R *.dfm}uses GDIPOBJ, GDIPAPI, TypInfo;procedure TForm1.FormCreate(Sender: TObject);var  i: Integer;begin  for i := 0 to 5 do    ComboBox1.Items.Add(GetEnumName(TypeInfo(TDashStyle), i));  ComboBox1.ItemIndex := 0;end;procedure TForm1.FormPaint(Sender: TObject);var  g: TGPGraphics;  p: TGPPen;begin  g := TGPGraphics.Create(Canvas.Handle);  g.Clear($FFFFFFFF);  p := TGPPen.Create(aclLimeGreen, 10);  p.SetDashStyle(TDashStyle(ComboBox1.ItemIndex));  g.DrawLine(p, 0, 0, ClientWidth, ClientHeight);  p.Free;  g.Free;end;procedure TForm1.ComboBox1Change(Sender: TObject);begin  Repaint;end;end.

表單檔案:

object Form1: TForm1  Left = 0  Top = 0  Caption = 'Form1'  ClientHeight = 167  ClientWidth = 242  Color = clBtnFace  Font.Charset = DEFAULT_CHARSET  Font.Color = clWindowText  Font.Height = -11  Font.Name = 'Tahoma'  Font.Style = []  OldCreateOrder = False  Position = poDesktopCenter  OnCreate = FormCreate  OnPaint = FormPaint  PixelsPerInch = 96  TextHeight = 13  object ComboBox1: TComboBox    Left = 89    Top = 8    Width = 145    Height = 21    ItemHeight = 13    TabOrder = 0    Text = 'ComboBox1'    OnChange = ComboBox1Change  endend

畫筆樣式枚舉的定義:

DashStyle = (  DashStyleSolid,      {指定實線}  DashStyleDash,       {指定由劃線段組成的直線}  DashStyleDot,        {指定由點構成的直線}  DashStyleDashDot,    {指定由重複的劃線點圖案構成的直線}  DashStyleDashDotDot, {指定由重複的劃線點點圖案構成的直線}  DashStyleCustom      {指定使用者定義的自訂劃線段樣式});TDashStyle = DashStyle;