lasterroru.pas

DelphiWin32核心API参考光盘内容.是学习书籍中的源码,便于学习.

unit LastErrorU;

interface

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

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.DFM}

procedure TForm1.Button1Click(Sender: TObject);
var
  ErrorCode: DWORD;   // holds our error code value
begin
  {set the last error code.  bit 29 is set to indicate
   an application defined error code, and the low order
   word is set to a decimal value of 100}
  SetLastError($20000064);

  {retrieve the last error code}
  ErrorCode := GetLastError;

  {display the code in the low order word}
  Button1.Caption := 'User Defined Error Code: '+IntToStr(LoWord(ErrorCode));
end;

end.