Delphi 2009 新增了泛型容器单元: Generics.Collections, 同时还有一个 Generics.Defaults 单元做支持.
Generics.Collections 包含了以下实用类:
TList<T>
TQueue<T>
TStack<T>
TDictionary<TKey,TValue>
TObjectList<T>
TObjectQueue<T>
TObjectStack<T>
TObjectDictionary<TKey,TValue>
有了以上泛型的容器, 恐怕 Classes.TList 和 Contnrs 单元下的 TObjectList 等系列容器也就只为兼容存在了.
Generics.Collections.TList<T> 既然是泛型的, 那肯定应该容得下字符串列表, 本例就依此测试吧.
如果你对泛型不了解, 应先看看: http://www.cnblogs.com/del/archive/2008/08/14/1268258.html
本例效果图:
代码文件:
unit Unit1; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; type TForm1 = class(TForm) Memo1: TMemo; Edit1: TEdit; Button1: TButton; Button2: TButton; Button3: TButton; Button4: TButton; Button5: TButton; Button6: TButton; Button7: TButton; Button8: TButton; Button9: TButton; Button10: TButton; procedure FormCreate(Sender: TObject); procedure FormDestroy(Sender: TObject); procedure Edit1Change(Sender: TObject); procedure Button1Click(Sender: TObject); procedure Button2Click(Sender: TObject); procedure Button3Click(Sender: TObject); procedure Button4Click(Sender: TObject); procedure Button5Click(Sender: TObject); procedure Button6Click(Sender: TObject); procedure Button7Click(Sender: TObject); procedure Button8Click(Sender: TObject); procedure Button9Click(Sender: TObject); procedure Button10Click(Sender: TObject); end; var Form1: TForm1; implementation {$R *.dfm} uses Generics.Collections; {Delphi 2009 新增的泛型容器单元} var List: TList<string>; {定义一个泛型 TList 类, 这指定了要用于 string} str: string = ‘Test‘; {建立} procedure TForm1.FormCreate(Sender: TObject); begin List := TList<string>.Create; Memo1.Clear; Edit1.Text := str; Button1.Caption := Button1.Caption + ‘ 显示‘; Button2.Caption := Button2.Caption + ‘ 添加‘; Button3.Caption := Button3.Caption + ‘ 插入‘; Button4.Caption := Button4.Caption + ‘ 删除1‘; Button5.Caption := Button5.Caption + ‘ 删除2‘; Button6.Caption := Button6.Caption + ‘ 查找‘; Button7.Caption := Button7.Caption + ‘ 排序‘; Button8.Caption := Button8.Caption + ‘ 翻转‘; Button9.Caption := Button9.Caption + ‘ 清空‘; Button10.Caption := Button10.Caption + ‘ 添加数组‘; end; {释放} procedure TForm1.FormDestroy(Sender: TObject); begin List.Free; end; procedure TForm1.Edit1Change(Sender: TObject); begin if Edit1.Text <> ‘‘ then str := Edit1.Text; end; {显示} procedure TForm1.Button1Click(Sender: TObject); var i: Integer; begin Memo1.Clear; for i := 0 to List.Count - 1 do Memo1.Lines.Add(List[i]); {List[i] = List.Item[i]} Text := Format(‘当前总数: %d‘, [List.Count]); end; {添加} procedure TForm1.Button2Click(Sender: TObject); begin List.Add(str); Button1.Click; {刷新显示} end; {插入, 譬如插入在最前面} procedure TForm1.Button3Click(Sender: TObject); begin List.Insert(0, str); Button1.Click; end; {根据序号删除, 譬如删除第一个数据} procedure TForm1.Button4Click(Sender: TObject); begin List.RemoveAt(0); Button1.Click; end; {根据内容删除, 譬如删除第一个数据} procedure TForm1.Button5Click(Sender: TObject); var s: string; begin s := List[0]; List.Remove(s); Button1.Click; end; {查找} procedure TForm1.Button6Click(Sender: TObject); var n: Integer; begin n := List.IndexOf(str); {LastIndexOf 是从后面找; 也可用 List.Contains(str) 判断是否包含 str} if n = -1 then ShowMessage(‘没找到‘) else ShowMessageFmt(‘%s 是第 %d 个‘, [str, n+1]); end; {排序} procedure TForm1.Button7Click(Sender: TObject); begin List.Sort; Button1.Click; end; {翻转} procedure TForm1.Button8Click(Sender: TObject); begin List.Reverse; Button1.Click; end; {清空} procedure TForm1.Button9Click(Sender: TObject); begin List.Clear; Button1.Click; end; {添加数组} procedure TForm1.Button10Click(Sender: TObject); const arr: array[0..2] of string = (‘CodeGear‘, ‘Delphi‘, ‘2009‘); begin List.Add(‘Embarcadero‘); List.AddRange(arr); Button1.Click; end; end.
窗体文件:
object Form1: TForm1 Left = 0 Top = 0 Caption = ‘Form1‘ ClientHeight = 201 ClientWidth = 349 Color = clBtnFace Font.Charset = DEFAULT_CHARSET Font.Color = clWindowText Font.Height = -11 Font.Name = ‘Tahoma‘ Font.Style = [] OldCreateOrder = False OnCreate = FormCreate OnDestroy = FormDestroy PixelsPerInch = 96 TextHeight = 13 object Memo1: TMemo Left = 0 Top = 0 Width = 121 Height = 201 Align = alLeft Lines.Strings = ( ‘Memo1‘) ScrollBars = ssBoth TabOrder = 0 ExplicitHeight = 206 end object Button1: TButton Left = 136 Top = 13 Width = 81 Height = 25 Caption = ‘Button1‘ TabOrder = 1 OnClick = Button1Click end object Button2: TButton Left = 127 Top = 44 Width = 100 Height = 25 Caption = ‘Button2‘ TabOrder = 2 OnClick = Button2Click end object Button3: TButton Left = 127 Top = 75 Width = 100 Height = 25 Caption = ‘Button3‘ TabOrder = 3 OnClick = Button3Click end object Button4: TButton Left = 127 Top = 106 Width = 100 Height = 25 Caption = ‘Button4‘ TabOrder = 4 OnClick = Button4Click end object Button5: TButton Left = 127 Top = 137 Width = 100 Height = 25 Caption = ‘Button5‘ TabOrder = 5 OnClick = Button5Click end object Button6: TButton Left = 240 Top = 44 Width = 100 Height = 25 Caption = ‘Button6‘ TabOrder = 6 OnClick = Button6Click end object Button7: TButton Left = 240 Top = 75 Width = 100 Height = 25 Caption = ‘Button7‘ TabOrder = 7 OnClick = Button7Click end object Button8: TButton Left = 240 Top = 106 Width = 100 Height = 25 Caption = ‘Button8‘ TabOrder = 8 OnClick = Button8Click end object Button9: TButton Left = 240 Top = 137 Width = 100 Height = 25 Caption = ‘Button9‘ TabOrder = 9 OnClick = Button9Click end object Edit1: TEdit Left = 240 Top = 15 Width = 100 Height = 21 TabOrder = 10 Text = ‘Edit1‘ OnChange = Edit1Change end object Button10: TButton Left = 127 Top = 168 Width = 214 Height = 25 Caption = ‘Button10‘ TabOrder = 11 OnClick = Button10Click end end
时间: 2024-10-10 20:59:13