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CRC校验算法 CRC校验算法 CRC校验算法 CRC校验算法

unit Unit1;

interface

uses
  SysUtils,  Forms, crc32, ComCtrls, StdCtrls, ExtCtrls, Classes,
  Controls, Dialogs;

type
  TForm1 = class(TForm)
    Panel1: TPanel;
    Button1: TButton;
    ProgressCRC: TProgressBar;
    OpenDialog1: TOpenDialog;
    Label1: TLabel;
    FileEdit: TEdit;
    CRC32Text: TEdit;
    procedure Button1Click(Sender: TObject);
    procedure AnalyzeFile(Filename: TFilename);
  private
    { private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

const NotCalc = '--Not Calculated--';

procedure UpdateProgress(Percent:Integer);
begin
  Form1.ProgressCRC.Position := Percent;
  Form1.Refresh;
  Application.ProcessMessages;
end;

procedure TForm1.AnalyzeFile(Filename: TFilename);
begin
  FileEdit.Text := Filename;
  Screen.Cursor := crHourGlass;
  Application.Title := 'Analyzing';
  ProgressCRC.Top := CRC32Text.Top;
  UpdateProgress(0);
  ProgressCRC.Visible := True;
  Form1.Refresh;
  try
    CRC32Text.Text := IntToHex(FileCRC32(FileName, @UpdateProgress), 8);
    if CRCError then CRC32Text.Text := 'Error';
  finally
    ProgressCRC.Visible := False;
    Form1.Refresh;
    Application.Title := 'CRC32: ' + ExtractFileName(Filename);
    Screen.Cursor := crDefault;
  end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
  if FileExists(Form1.Caption) then OpenDialog1.FileName := Form1.Caption;
  if OpenDialog1.Execute then AnalyzeFile(OpenDialog1.Filename);
end;

end.