unitfrmmain.pas

《Delphi实用程序100例》配套书源码盘

unit unitFrmMain;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  ComCtrls, StdCtrls;

type
  TForm1 = class(TForm)
    DateTimePicker1: TDateTimePicker;
    DateTimePicker2: TDateTimePicker;
    DateTimePicker3: TDateTimePicker;
    DateTimePicker4: TDateTimePicker;
    OpenDialog1: TOpenDialog;
    Button1: TButton;
    Button2: TButton;
    Memo1: TMemo;
    Label1: TLabel;
    Label2: TLabel;
    procedure Button1Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}
// 转换文件的时间格式

function CovFileDate(FileDate: _FileTime): TDateTime;
var
  Tct: _SystemTime;
  Temp: _FileTime;
begin
  FileTimeToLocalFileTime(FileDate, Temp);
  FileTimeToSystemTime(Temp, Tct);
  CovFileDate := SystemTimeToDateTime(Tct);
end;

// 获取文件时间，fn表示目标文件路径和名称,fType为取得日期的类型

function GetFileTime(const fn: string; const fType: Byte): string;
const
  Model = 'yyyy/mm/dd,hh:mm:ss'; { 设定时间格式 }
var
  Tp: TSearchRec; { 声明Tp为一个查找记录 }


begin
  FindFirst(fn, faAnyFile, Tp); { 查找目标文件 }
  // 返回文件的创建时间
  if fType = 1 then
    Result := FormatDateTime(Model, CovFileDate(Tp.FindData.ftCreationTime));
  // 返回文件的修改时间
  if fType = 2 then
    Result := FormatDateTime(Model, CovFileDate(Tp.FindData.ftLastWriteTime));
  //返回文件的当前访问时间
  if fType = 3 then
    Result := FormatDateTime(Model, Now);

  FindClose(Tp);
end;

procedure SetFileDateTime(const Tf: string);
{ 设置文件时间，Tf表示目标文件路径和名称 }
var
  Dt1, Dt2: Integer;
  Fs: TFileStream;
  Fct, Flt: TFileTime;
begin
  Dt1 := DateTimeToFileDate(
    Trunc(Form1.DateTimePicker1.Date) + Frac(Form1.DateTimePicker2.Time));
  Dt2 := DateTimeToFileDate(
    Trunc(Form1.DateTimePicker3.Date) + Frac(Form1.DateTimePicker4.Time));
  // 转换用户输入在DataTimePicker中的信息
  try
    FS := TFileStream.Create(Tf, fmOpenReadWrite);
    try
      if DosDateTimeToFileTime(LongRec(DT1).Hi, LongRec(DT1).Lo, Fct) and
        LocalFileTimeToFileTime(Fct, Fct) and
        DosDateTimeToFileTime(LongRec(DT2).Hi, LongRec(DT2).Lo, Flt) and
        LocalFileTimeToFileTime(Flt, Flt)
        then
        // 设置文件时间属性
        SetFileTime(FS.Handle, @Fct, @Flt, @Flt);
    finally
      begin
        FS.Free;
        ShowMessage('修改成功');
      end;
    end;
  except
    // 因为目标文件正在被使用等原因而导致失败
    MessageDlg('日期修改操作失败！',
      mtError, [mbOk], 0);
  end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  if OpenDialog1.Execute then
    begin
      Memo1.Clear;
      Memo1.Lines.Add('文件创建日期:' + GetFileTime(OpenDialog1.FileName, 1));
      Memo1.Lines.Add('文件修改日期:' + GetFileTime(OpenDialog1.FileName, 2));
      Memo1.Lines.Add('文件访问日期:' + GetFileTime(OpenDialog1.FileName, 3));
    end;
end;

procedure TForm1.Button3Click(Sender: TObject);
begin
  OpenDialog1.Execute;
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
  if OpenDialog1.Execute then
    SetFileDateTime(OpenDialog1.FileName);
end;

end.