带进度的文件复制 - 回复 "冷风无泪" 的问题

问题来源: http://www.cnblogs.com/del/archive/2008/12/02/1066817.html#1389078

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本例效果图:

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代码文件:

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unit Unit1;interfaceuses  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,  Dialogs, StdCtrls, ComCtrls;type  TForm1 = class(TForm)    Button1: TButton;    ProgressBar1: TProgressBar;    procedure Button1Click(Sender: TObject);  end;var  Form1: TForm1;implementation{$R *.dfm}procedure TForm1.Button1Click(Sender: TObject);const  getPath = 'c:\temp\get.rar';  setPath = 'c:\temp\set.rar';var  getStream,setStream: TFileStream;  num, n: Integer;  buf: PByte;  BufSize,block: Integer;begin  if not FileExists(getPath) then  begin    ShowMessage('源文件不存在');    Exit;  end;  getStream := TFileStream.Create(getPath, fmOpenRead or fmShareExclusive);  setStream := TFileStream.Create(setPath, fmCreate);  num := getStream.Size;  setStream.Size := num;  getStream.Position := 0;  setStream.Position := 0;  BufSize := num;  block := BufSize div 100;  GetMem(buf, BufSize);  ProgressBar1.Max := 100;  ProgressBar1.Min := 0;  ProgressBar1.Position := 0;  while num <> 0 do  begin    Application.ProcessMessages;    n := block;    if n > num then n := num;    getStream.ReadBuffer(buf^, n);    setStream.WriteBuffer(buf^, n);    ProgressBar1.Position := Trunc((1 - num / BufSize) * 100);    Dec(num, n);  end;  FreeMem(buf, BufSize);  getStream.Free;  setStream.Free;  ShowMessage('复制完毕');  ProgressBar1.Position := 0;end;end.

窗体文件:

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object Form1: TForm1  Left = 0  Top = 0  Caption = 'Form1'  ClientHeight = 104  ClientWidth = 265  Color = clBtnFace  Font.Charset = DEFAULT_CHARSET  Font.Color = clWindowText  Font.Height = -11  Font.Name = 'Tahoma'  Font.Style = []  OldCreateOrder = False  Position = poDesktopCenter  PixelsPerInch = 96  TextHeight = 13  object Button1: TButton    Left = 96    Top = 56    Width = 75    Height = 25    Caption = 'Button1'    TabOrder = 0    OnClick = Button1Click  end  object ProgressBar1: TProgressBar    Left = 8    Top = 16    Width = 249    Height = 17    TabOrder = 1  endend