windows NT/2000读写物理，逻辑磁盘扇区

procedure TForm1.Button1Click(Sender: TObject);
var
hDriveHandle: THandle;
procedure TForm1.Button1Click(Sender: TObject);
const
BytesPerSector = 512;
SectorCount = 1; //读写扇区数
SectorStart = 0; //起始扇区数
drive = '//./C:'; //驱动盘
var
str: String;
p: PChar;
i: Cardinal;
begin
hDriveHandle := CreateFile(drive, GENERIC_ALL, FILE_SHARE_READ or FILE_SHARE_WRITE,
nil, OPEN_EXISTING, 0, 0);
if (hDriveHandle <> INVALID_HANDLE_VALUE) then
begin
p := allocmem(SectorCount * ByteSPerSector);//p 必须是新申请的内存或全局变量，不能是局部变量
//定义为局部变量是不能读写磁盘的
FileSeek(hDriveHandle, SectorStart * BytesPerSector, 0); //起始扇区
if FileRead(hDriveHandle, p[0], SectorCount * BytesperSector)<> //读扇区
SectorCount * BytesperSector then
raise Exception.Create('Read Error!');
str :='';
for i := 0 to 512 - 1 do
begin
str := str + Format('%.2x', [integer(p[i])]);
if i mod 16 = 15 then
str := str + #13;
end;
ShowMessage(str);

FileSeek(hDriveHandle, SectorStart * BytesPerSector, 0); //起始扇区
if FileWrite(hDriveHandle, p[0], SectorCount * BytesperSector)<> //写扇区
SectorCount * BytesperSector then
raise Exception.Create('Write Error!');

FreeMem(p, SectorCount * BytesperSector);
Closehandle(hDriveHandle);
end;
end;

procedure TForm1.Button2Click(Sender: TObject);
const
BytesPerSector = 512;
SectorCount = 1; //读写扇区数
SectorStart = 0; //起始扇区数
drive = '//./PHYSICALDRIVE0'; //物理磁盘
var
str: String;
p: PChar;
i: Cardinal;
begin
hDriveHandle := CreateFile(drive, GENERIC_ALL, FILE_SHARE_READ or FILE_SHARE_WRITE,
nil, OPEN_EXISTING, 0, 0);
if (hDriveHandle <> INVALID_HANDLE_VALUE) then
begin
p := allocmem(SectorCount * ByteSPerSector);//p 必须是新申请的内存或全局变量，不能是局部变量
//定义为局部变量是不能读写磁盘的
FileSeek(hDriveHandle, SectorStart * BytesPerSector, 0); //起始扇区
if FileRead(hDriveHandle, p[0], SectorCount * BytesperSector)<> //读扇区
SectorCount * BytesperSector then
raise Exception.Create('Read Error!');
str :='';
for i := 0 to 512 - 1 do
begin
str := str + Format('%.2x', [integer(p[i])]);
if i mod 16 = 15 then
str := str + #13;
end;
ShowMessage(str);

FileSeek(hDriveHandle, SectorStart * BytesPerSector, 0); //起始扇区
if FileWrite(hDriveHandle, p[0], SectorCount * BytesperSector)<> //写扇区
SectorCount * BytesperSector then
raise Exception.Create('Write Error!');

FreeMem(p, SectorCount * BytesperSector);
Closehandle(hDriveHandle);
end;
end;