[转载]Delphi2010新功能:TDirectory.TFilterPredicate

原文地址：Delphi2010新功能:TDirectory.TFilterPredicate作者：StremWang

Delphi 2010 新增功能之: IOUtils 单元: TDirectory.TFilterPredicate

TDirectory.GetFiles 函数还有一个 TDirectory.TFilterPredicate 类型的参数, 这是个匿名函数类型, 可对搜索结果再处理.

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unit Unit1;

interface

uses

  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,

  Dialogs, StdCtrls;

type

  TForm1 = class(TForm)

    Memo1: TMemo;

    Button1: TButton;

    Button2: TButton;

    Button3: TButton;

    Button4: TButton;

    procedure Button1Click(Sender: TObject);

    procedure Button2Click(Sender: TObject);

    procedure Button3Click(Sender: TObject);

    procedure Button4Click(Sender: TObject);

  end;

var

  Form1: TForm1;

implementation

{$R *.dfm}

uses IOUtils, Types;

const path = 'C:Program FilesEmbarcaderoRAD Studio7.0';

//准备给 TDirectory.GetFiles 调用的函数, 须符合 TDirectory.TFilterPredicate 格式

function fp(const Path: string; const SearchRec: TSearchRec): Boolean;

begin

  Form1.Memo1.Lines.Add(Path + '' + SearchRec.Name);

end;

procedure TForm1.Button1Click(Sender: TObject);

var

  files: TStringDynArray;

begin

  Memo1.Clear;

  files := TDirectory.GetFiles(path, fp);

end;

procedure TForm1.Button2Click(Sender: TObject);

var

  files: TStringDynArray;

begin

  Memo1.Clear;

  files := TDirectory.GetFiles(path, '*.txt', fp);

end;

procedure TForm1.Button3Click(Sender: TObject);

var

  files: TStringDynArray;

begin

  Memo1.Clear;

  files := TDirectory.GetFiles(path, '*.txt', TSearchOption.soAllDirectories, fp);

end;

//可以这样方便地使用匿名函数

procedure TForm1.Button4Click(Sender: TObject);

var

  files: TStringDynArray;

begin

  Memo1.Clear;

  files := TDirectory.GetFiles(path,

    function(const Path: string; const SearchRec: TSearchRec): Boolean

    begin

      Memo1.Lines.Add(Path + '' + SearchRec.Name);

    end

  );

end;

end.