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

时间:2021-11-04 12:25:48

转自: http://hi.baidu.com/ddhx2008/blog/item/39f97c0011dbcd0f738da5b1.html

Delphi 2010 新增功能之: IOUtils 单元(2): TDirectory.TFilterPredicate2010-04-04 18:02TDirectory.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. 
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 Files\Embarcadero\RAD Studio\7.0'; 
 
//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.