[求助]DELPHI的编译问题

小弟是个刚学DELPHI的菜鸟，今天根据课本的一个编程例子来做了个程序，代码如下：
unit Unit1;

interface

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

type
TForm1 = class(TForm)
Label1: TLabel;
Edit1: TEdit;
Button1: TButton;
CheckBox1: TCheckBox;
CheckBox2: TCheckBox;
CheckBox3: TCheckBox;
CheckBox4: TCheckBox;
CheckBox5: TCheckBox;
CheckBox6: TCheckBox;
CheckBox7: TCheckBox;
StringGrid1: TStringGrid;
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
sr:tsearchrec;
fileattrs:integer;
begin
stringgrid1.Rowcount:=1;
if checkbox1.Checked then
fileattrs:=fareadonly
else
fileattrs:=0;

if checkbox2.Checked then
fileattrs:=fileattrs+fahidden;

if checkbox3.Checked then
fileattrs:=fileattrs+fasysfile;

if checkbox4.Checked then
fileattrs:=fileattrs+favolumeid;

if checkbox5.Checked then
fileattrs:=fileattrs+fadirectory;

if checkbox6.Checked then
fileattrs:=fileattrs+faarchive;

if checkbox7.Checked then
fileattrs:=fileattrs+faanyfile;
with stringgrid1 do
begin
rowcount:=0;
if findfirst(edit1.text,fileattrs,sr) - 0 then
begin
cells(1，0):='文件名';
cells(2,0):='大小（K）'；

repeat
if(sr.attr and fileattrs)=sr.attr then
begin
rowcount:=rowcount+1;
cells(1,rowcount-1):=sr.Name;
cells(2,rowcount-1):=inttostr(SR.Size);
end;
UNIT findnext(sr)<>0;
findclose(sr);
end;
end;
end;

end.
可编译时老是出现下面的错误提示：
[Warning]Unit1.pas(43):Symbol'faReadOnly'is specific to a platform
[Warning]Unit1.pas(48):Symbol'faHidden'is specific to a platform
[Warning]Unit1.pas(51):Symbol'faSysFile'is specific to a platform
[Warning]Unit1.pas(54):Symbol'faVolumeID'is specific to a platform
[Warning]Unit1.pas(60):Symbol'faArchive'is specific to a platform
[Error]Unit1.pas(67):Type of expression must be BOOLEAN
[Error]Unit1.pas(69):'['expected but '('found
[Error]Unit1.pas(70):'['expected but '('found
[Error]Unit1.pas(70):lllegal character in input file:';'($A3BB)
[Error]Unit1.pas(72):Missing operator or semicolon
[Error]Unit1.pas(76):'['expected but '('found
[Error]Unit1.pas(76):Left side cannot be assigned to
[Error]Unit1.pas(77):'['expected but '('found
[Error]Unit1.pas(77):Left side cannot be assigned to
[Error]Unit1.pas(79):Statement expected but 'UNIT'found
[Error]Unit1.pas(79):Statement expected,but expression of type 'Boolean'found
[Error]Unit1.pas(81):'UNTIL'expected but 'END' found
[Fatal Error]Project1.dpr(5):Could not compile used unit'Unit1.pas'
这是为什么呀，请各位高手帮忙看看，小弟在这先谢过大家了