====================================
File-management routines 档案管理常式
====================================
--------------------------------------------------------
ChangeFileExt 变更档案的副档名
--------------------------------------------------------
Unit SysUtils
函数原型 function ChangeFileExt(const FileName, Extension: string):
string;
范例 procedure TForm1.Button1Click(Sender: TObject);
var
S: String;
P1:String;
P2:String;
begin
P1:='abc.txt';
P2:='.ini';
S := ChangeFileExt(P1,P2);
Label1.Caption:=S;
end;

结果 S== 'abc.ini'

P1:='abc'
P2:='.ini'
S== 'abc.ini'

P1:='c:\windows\abc.txt'
P2:='.ini'
S=='c:\windows\abc.ini'

P1:='abc.txt'
P2:='ini'
S=='abcini'
**注意:P2的第一位元必须有一点'.ini'

范例
procedure TForm1.ConvertIcon2BitmapClick(Sender: TObject);

var
s : string;
Icon: TIcon;
begin

OpenDialog1.DefaultExt := '.ICO';

OpenDialog1.Filter := 'icons (*.ico)|*.ICO';
OpenDialog1.Options := [ofOverwritePrompt, ofFileMustExist, ofHideReadOnly ];
if OpenDialog1.Execute then
begin
Icon := TIcon.Create;
try
Icon.Loadfromfile(OpenDialog1.FileName);
s:= ChangeFileExt(OpenDialog1.FileName,'.BMP');
Image1.Width := Icon.Width;
Image1.Height := Icon.Height;
Image1.Canvas.Draw(0,0,Icon);
Image1.Picture.SaveToFile(s);

ShowMessage(OpenDialog1.FileName + ' Saved to ' + s);
finally
Icon.Free;
end;
end;
end;
# SaveToFile, Create, Height, Width, Canvas, ChangeFileExt example

--------------------------------------------------------
ExpandFileName 将档案名称加在目前所在之路径全名之後
--------------------------------------------------------
Unit SysUtils
函数原型 function ExpandFileName(const FileName: string): string;
说明 设目前目录为 c:\windows 档案名称为 abc.txt
则结果为 c:\windows\abc.txt
**** 此函数并不是求abc.txt的所在路径.
范例 procedure TForm1.Button1Click(Sender: TObject);
var
S: String;
begin
S:=ExpandFileName('abc.txt');
Label1.Caption:=S;
end;
范例
procedure TForm1.Button1Click(Sender: TObject)
begin
ListBox1.Items.Add(ExpandFileName(Edit1.Text));
end;

------------------------------------------------------------------
DirectoryExists 目录是否存在------------------------------------------------------------------
Unit
FileCtrl

uses FileCtrl;

procedure TForm1.Button1Click(Sender: TObject);
begin
if not DirectoryExists('c:\temp') then
if not CreateDir('C:\temp') then
raise Exception.Create('Cannot create c:\temp');
end;
--------------------------------------------------------
ForceDirectories 目录
---------------------------------------------------------
Unit FileCtrl
函数原型 function ForceDirectories(Dir: string): Boolean;

procedure TForm1.Button1Click(Sender: TObject);
var
Dir: string;
begin
Dir := 'C:\APPS\SALES\LOCAL';
if DirectoryExists(Dir) then
Label1.Caption := Dir + ' was created'
end;

--------------------------------------------------------
ExpandUNCFileName 同上(只是得到网路上的路径)
--------------------------------------------------------
Unit SysUtils
函数原型 function ExpandUNCFileName(const FileName: string):string;
ExtractFileDir 分析字串中的路径
Unit SysUtils
函数原型 function ExtractFileDir(const FileName: string): string;
说明 设S字串为 c:\windows\abc.txt
则结果为 c:\windows
**** 功能在於由任何部份传来的叁数,加以分析它的路径
范例 procedure TForm1.Button1Click(Sender: TObject);
var
S: String;
P1:String;
begin
P1:='c:\windows\abc.txt';
S:=ExtractFileDir(P1);
Label1.Caption:=S;
end;

S=='c:\windows'

P1:='abc.txt'
S=='

P1:='c:abc.txt'
S=='c:'

P1:='c:\abc.txt'
S=='c:\'
--------------------------------------------------------
ExtractFileDrive 分析字串中的磁碟机名称
--------------------------------------------------------
Unit SysUtils
函数原型 function ExtractFileDrive(const FileName: string): string;
**** 功能同上,只是传回磁碟机名称.
范例 procedure TForm1.Button1Click(Sender: TObject);
var
S: String;
P1:String;
begin
P1:='c:\windows\abc.txt';
S:=ExtractFileDrive(P1);
Label1.Caption:=S;
end;

S:='c:'

P1:='abc.txt'
S=='
--------------------------------------------------------
ExtractFileExt 分析字串中的档案名称的副档名
--------------------------------------------------------
Unit SysUtils
函数原型 function ExtractFileExt(const FileName: string): string;
范例 procedure TForm1.Button1Click(Sender: TObject);
var

S: String;
P1:String;
begin
P1:='c:\windows\abc.txt';
S:=ExtractFileExt(P1);
Label1.Caption:=S;
end;

S=='.txt'

P1:='c:\windows\abc'
S=='
范例 MyFilesExtension := ExtractFileExt(MyFileName);
--------------------------------------------------------
ExtractFileName 分析字串中的档案名称(只传回档案名称)
--------------------------------------------------------
Unit SysUtils
函数原型 function ExtractFileName(const FileName: string): string;
范例 procedure TForm1.Button1Click(Sender: TObject);
var
S: String;
P1:String;
begin
P1:='c:\windows\abc.txt';
S:=ExtractFileName(P1);
Label1.Caption:=S;
end;

S=='abc.txt'
范例
procedure TForm1.Button1Click(Sender: TObject);
var
BackupName: string;
FileHandle: Integer;
StringLen: Integer;
X: Integer;
Y: Integer;
begin
if SaveDialog1.Execute then
begin
if FileExists(SaveDialog1.FileName) then
begin
BackupName := ExtractFileName(SaveDialog1.FileName);
BackupName := ChangeFileExt(BackupName, '.BAK');
if not RenameFile(SaveDialog1.FileName, BackupName) then
raise Exception.Create('Unable to create backup file.');
end;
FileHandle := FileCreate(SaveDialog1.FileName);
{ Write out the number of rows and columns in the grid. }
FileWrite(FileHandle,
StringGrid1.ColCount, SizeOf(StringGrid1.ColCount));
FileWrite(FileHandle,
StringGrid1.RowCount, SizeOf(StringGrid1.RowCount));
for X := 0 to StringGrid1.ColCount ? 1 do
begin
for Y := 0 to StringGrid1.RowCount ? 1 do
begin
{ Write out the length of each string, followed by the string itself. }
StringLen := Length(StringGrid1.Cells[X,Y]);
FileWrite(FileHandle, StringLen, SizeOf(StringLen));
FileWrite(FileHandle,
StringGrid1.Cells[X,Y], Length(StringGrid1.Cells[X,Y]);
end;
end;
FileClose(FileHandle);
end;
end;
##FileExists, RenameFile, FileCreate, FileWrite, FileClose, ExtractFileName Example

--------------------------------------------------------
ExtractFilePath 分析字串中的路径
--------------------------------------------------------
Unit SysUtils
函数原型 function ExtractFilePath(const FileName: string): string;
说明 设S字串为 c:\windows\abc.txt
则结果为 c:\windows范例 procedure TForm1.Button1Click(Sender: TObject);
var
S: String;
P1:String;
begin
P1:='c:\windows\abc.txt';
S:=ExtractFilePath(P1);
Label1.Caption:=S;
end;
范例
begin
with Session do
begin
ConfigMode := cmSession;

try
AddStandardAlias('TEMPDB', ExtractFilePath(ParamStr(0)), 'PARADOX');
finally
ConfigMode := cmAll;
end;
end;
##ConfigMode, AddStandardAlias, ExtractFilePath example
--------------------------------------------------------
FileSearch 寻找档案在磁碟机中的正确路径
--------------------------------------------------------
Unit SysUtils
函数原型 function FileSearch(const Name, DirList: string): string;
范例 var
s:string;
begin
s:= FileSearch('abc.txt', 'c:\window\');
Label1.Caption:=s;
end;
说明 找到传回c:\window\abc.txt 找不到传回空字串.
范例
procedure TForm1.Button1Click(Sender: TObject);
var
buffer: array [0..255] of char;
FileToFind: string;
begin
GetWindowsDirectory(buffer, SizeOf(buffer));
FileToFind := FileSearch(Edit1.Text, GetCurrentDir + ';' + buffer);
if FileToFind = ' then
ShowMessage('Couldn't find ' + Edit1.Text + '.')
else
ShowMessage('Found ' + FileToFind + '.');
end;
##FileSearch, ShowMessage Example

--------------------------------------------------------
FileAge 传回档案的日期及时间(DOS型态).
--------------------------------------------------------
Unit SysUtils
函数原型 function FileAge(const FileName: string): Integer;
说明 就是档案总管中档案内容裹面的修改日期.
范例 procedure TForm1.Button1Click(Sender: TObject);
var
S: String;
FileDate1:Integer;
DateTime1:TDateTime;

begin
FileDate1 := FileAge('c:\delphi_d\delphi_help1.txt');
DateTime1 := FileDateToDateTime(FileDate1);
S := DateTimeToStr(DateTime1);
Label1.Caption:=S;
end;
--------------------------------------------------------
FileDateToDateTime 将DOS型态的日期时间转换为TDateTime型态.
--------------------------------------------------------
Unit SysUtils
函数原型 function FileDateToDateTime(FileDate: Integer):TDateTime;
-----------------------------------------------------------------------------
DateTimeToFileDate 将TDateTime型态的日期时间转换为 DOS型态.
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function DateTimeToFileDate(DateTime: TDateTime):Integer;
FileGetDate 传回档案的日期及时间(DOS型态).
Unit SysUtils
函数原型 function FileGetDate(Handle: Integer): Integer;
说明 就是档案总管中档案内容裹面的修改日期.
范例 procedure TForm1.Button1Click(Sender: TObject);
var
FileHandle:Integer;
S: String;
FileDate1:Integer;
DateTime1:TDateTime;
begin
FileHandle :=FileOpen('c:\delphi_d\delphi_help2.txt',
fmOpenReadWrite);
if FileHandle > 0 then
Begin
FileDate1 := FileGetDate(FileHandle);
DateTime1 := FileDateToDateTime(FileDate1);
S := DateTimeToStr(DateTime1);
FileClose(FileHandle);
End
else
S := 'Open File Error';
Label1.Caption:=S;
end;

-----------------------------------------------------------------------------
FileSetDate 设定档案的日期及时间(DOS型态).
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function FileSetDate(Handle: Integer; Age: Integer): Integer;
说明 传回值为0表示成功.
-----------------------------------------------------------------------------
DeleteFile 删除档案
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function DeleteFile(const FileName: string): Boolean;
范例 一 DeleteFile('DELETE.ME');

范例 二 if FileExists(FileName) then
if MessageDlg('Do you really want to delete ' +
ExtractFileName(FileName) + '?'), []) = IDYes then
DeleteFile(FileName);
##FileExists, DeleteFile Example
-----------------------------------------------------------------------------
RenameFile 更改档名
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function RenameFile(const OldName, NewName: string):Boolean;
范例
procedure TForm1.Button1Click(Sender: TObject);
var
BackupName: string;
FileHandle: Integer;
StringLen: Integer;
X: Integer;
Y: Integer;
begin
if SaveDialog1.Execute then
begin
if FileExists(SaveDialog1.FileName) then
begin
BackupName := ExtractFileName(SaveDialog1.FileName);
BackupName := ChangeFileExt(BackupName, '.BAK');
if not RenameFile(SaveDialog1.FileName, BackupName) then
raise Exception.Create('Unable to create backup file.');
end;
FileHandle := FileCreate(SaveDialog1.FileName);
{ Write out the number of rows and columns in the grid. }
FileWrite(FileHandle,
StringGrid1.ColCount, SizeOf(StringGrid1.ColCount));
FileWrite(FileHandle,
StringGrid1.RowCount, SizeOf(StringGrid1.RowCount));
for X := 0 to StringGrid1.ColCount ? 1 do

begin
for Y := 0 to StringGrid1.RowCount ? 1 do
begin
{ Write out the length of each string, followed by the string itself. }
StringLen := Length(StringGrid1.Cells[X,Y]);
FileWrite(FileHandle, StringLen, SizeOf(StringLen));
FileWrite(FileHandle,
StringGrid1.Cells[X,Y], Length(StringGrid1.Cells[X,Y]);
end;
end;
FileClose(FileHandle);
end;
end;
-----------------------------------------------------------------------------
DiskFree 磁碟机剩馀空间(Bytes)
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function DiskFree(Drive: Byte): Integer;
范例 var
S: string;
begin
S := IntToStr(DiskFree(0) div 1024) + ' Kbytes free.';
Label1.Caption:=S;
end;
说明 Drive
0=目前磁碟机,1=A磁碟机,2=B磁碟机...传回值若为-1,表示磁碟机侦测错误.
范例
var
S: string;
AmtFree: Int64;
Total: Int64;
begin
AmtFree := DiskFree(0);
Total := DiskSize(0);
S := IntToStr(AmtFree div Total) + 'percent of the space on drive 0 is free: ' (AmtFree div 1024) + ' Kbytes free. ';
Canvas.TextOut(10, 10, S);
end;
##DiskFree, DiskSize Example

-----------------------------------------------------------------------------
DiskSize 磁碟机空间大小(Bytes)
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function DiskSize(Drive: Byte): Integer;
范例 var
S: string;
begin
S := IntToStr(DiskSize(0) div 1024) + ' Kbytes free.';
Label1.Caption:=S;
end;
说明 Drive
0=目前磁碟机,1=A磁碟机,2=B磁碟机....传回值若为-1,表示磁碟机侦测错误.
##DiskFree, DiskSize Example
-----------------------------------------------------------------------------
FileExists 判断档案是否存在.
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function FileExists(const FileName: string): Boolean;
类似 FileExists, RenameFile, FileCreate, FileWrite, FileClose, ExtractFileName Example
范例
procedure TForm1.Button1Click(Sender: TObject);
var
BackupName: string;
FileHandle: Integer;
StringLen: Integer;
X: Integer;
Y: Integer;
begin
if SaveDialog1.Execute then
begin
if FileExists(SaveDialog1.FileName) then
begin
BackupName := ExtractFileName(SaveDialog1.FileName);
BackupName := ChangeFileExt(BackupName, '.BAK');
if not RenameFile(SaveDialog1.FileName, BackupName) then
raise Exception.Create('Unable to create backup file.');
end;
FileHandle := FileCreate(SaveDialog1.FileName);
{ Write out the number of rows and columns in the grid. }
FileWrite(FileHandle,
StringGrid1.ColCount, SizeOf(StringGrid1.ColCount));
FileWrite(FileHandle,
StringGrid1.RowCount, SizeOf(StringGrid1.RowCount));
for X := 0 to StringGrid1.ColCount ? 1 do
begin
for Y := 0 to StringGrid1.RowCount ? 1 do
begin
{ Write out the length of each string, followed by the string itself. }
StringLen := Length(StringGrid1.Cells[X,Y]);

FileWrite(FileHandle, StringLen, SizeOf(StringLen));
FileWrite(FileHandle,
StringGrid1.Cells[X,Y], Length(StringGrid1.Cells[X,Y]);
end;
end;
FileClose(FileHandle);
end;
end;
##FileExists, DeleteFile Example
##FileExists, RenameFile, FileCreate, FileWrite, FileClose, ExtractFileName Example
-----------------------------------------------------------------------------
FileOpen 开档.
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function FileOpen(const FileName: string; Mode:
Integer):Integer;
**** 开档失败传回-1.
说明 以下有关档案读取都属低阶,如Dos Int 21h中有关档案的部
分.
fmOpenRead = $0000;
fmOpenWrite = $0001;
fmOpenReadWrite = $0002;
fmShareCompat = $0000;
fmShareExclusive = $0010;
fmShareDenyWrite = $0020;
fmShareDenyRead = $0030;
fmShareDenyNone = $0040;

fmOpenRead Open for read access only.
FmOpenWrite Open for write access only.
FmOpenReadWrite Open for read and write access.
fmShareCompat Compatible with the way FCBs are
opened.
fmShareExclusive Read and write access is denied.
fmShareDenyWrite Write access is denied.
fmShareDenyRead Read access is denied.
fmShareDenyNone Allows full access for others.
范例
procedure OpenForShare(const FileName: String);
var
FileHandle : Integer;
begin
FileHandle := FileOpen(FileName, fmOpenWrite or fmShareDenyNone);
if FileHandle > 0 then
{valid file handle}
else
{Open error: FileHandle = negative DOS error code}
end;
范例
procedure TForm1.Button1Click(Sender: TObject);
var
iFileHandle: Integer;
iFileLength: Integer;
iBytesRead: Integer;
Buffer: PChar;
i: Integer
begin
if OpenDialog1.Execute then
begin
try
iFileHandle := FileOpen(OpenDialog1.FileName, fmOpenRead);
iFileLength := FileSeek(iFileHandle,0,2);
FileSeek(iFileHandle,0,0);
Buffer := PChar(AllocMem(iFileLength + 1));
iBytesRead = FileRead(iFileHandle, Buffer, iFileLength);
FileClose(iFileHandle);
for i := 0 to iBytesRead-1 do
begin
StringGrid1.RowCount := StringGrid1.RowCount + 1;
StringGrid1.Cells[1,i+1] := Buffer[i];
StringGrid1.Cells[2,i+1] := IntToStr(Integer(Buffer[i]));
end;
finally
FreeMem(Buffer);
end;
end;
end;
##FileOpen, FileSeek, FileRead Example

-----------------------------------------------------------------------------
FileCreate 建档
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function FileCreate(const FileName: string): Integer;

范例
procedure TForm1.Button1Click(Sender: TObject);
var
BackupName: string;

FileHandle: Integer;
StringLen: Integer;
X: Integer;
Y: Integer;
begin
if SaveDialog1.Execute then
begin
if FileExists(SaveDialog1.FileName) then
begin
BackupName := ExtractFileName(SaveDialog1.FileName);
BackupName := ChangeFileExt(BackupName, '.BAK');
if not RenameFile(SaveDialog1.FileName, BackupName) then

raise Exception.Create('Unable to create backup file.');
end;
FileHandle := FileCreate(SaveDialog1.FileName);
{ Write out the number of rows and columns in the grid. }
FileWrite(FileHandle,
StringGrid1.ColCount, SizeOf(StringGrid1.ColCount));
FileWrite(FileHandle,
StringGrid1.RowCount, SizeOf(StringGrid1.RowCount));
for X := 0 to StringGrid1.ColCount ? 1 do
begin

for Y := 0 to StringGrid1.RowCount ? 1 do
begin
{ Write out the length of each string, followed by the string itself. }
StringLen := Length(StringGrid1.Cells[X,Y]);
FileWrite(FileHandle, StringLen, SizeOf(StringLen));
FileWrite(FileHandle,
StringGrid1.Cells[X,Y], Length(StringGrid1.Cells[X,Y]);
end;
end;
FileClose(FileHandle);
end;

end;
##FileExists, RenameFile, FileCreate, FileWrite, FileClose, ExtractFileName Example
-----------------------------------------------------------------------------
FileClose 关档
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 procedure FileClose(Handle: Integer);
范例

procedure TForm1.Button1Click(Sender: TObject);
var
BackupName: string;
FileHandle: Integer;
StringLen: Integer;
X: Integer;
Y: Integer;
begin
if SaveDialog1.Execute then
begin
if FileExists(SaveDialog1.FileName) then
begin
BackupName := ExtractFileName(SaveDialog1.FileName);
BackupName := ChangeFileExt(BackupName, '.BAK');
if not RenameFile(SaveDialog1.FileName, BackupName) then
raise Exception.Create('Unable to create backup file.');
end;
FileHandle := FileCreate(SaveDialog1.FileName);
{ Write out the number of rows and columns in the grid. }
FileWrite(FileHandle,
StringGrid1.ColCount, SizeOf(StringGrid1.ColCount));
FileWrite(FileHandle,
StringGrid1.RowCount, SizeOf(StringGrid1.RowCount));
for X := 0 to StringGrid1.ColCount ? 1 do
begin
for Y := 0 to StringGrid1.RowCount ? 1 do
begin
{ Write out the length of each string, followed by the string itself. }
StringLen := Length(StringGrid1.Cells[X,Y]);
FileWrite(FileHandle, StringLen, SizeOf(StringLen));
FileWrite(FileHandle,
StringGrid1.Cells[X,Y], Length(StringGrid1.Cells[X,Y]);
end;
end;
FileClose(FileHandle);
end;
end;
##FileExists, RenameFile, FileCreate, FileWrite, FileClose, ExtractFileName Example

============================================
**** 它是以Handle为叁数.
============================================
FileRead 读取档案
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function FileRead(Handle: Integer; var Buffer; Count: Integer):Integer;
范例
procedure TForm1.Button1Click(Sender: TObject);

var
iFileHandle: Integer;
iFileLength: Integer;
iBytesRead: Integer;
Buffer: PChar;
i: Integer
begin
if OpenDialog1.Execute then
begin
try
iFileHandle := FileOpen(OpenDialog1.FileName, fmOpenRead);
iFileLength := FileSeek(iFileHandle,0,2);
FileSeek(iFileHandle,0,0);
Buffer := PChar(AllocMem(iFileLength + 1));
iBytesRead = FileRead(iFileHandle, Buffer, iFileLength);
FileClose(iFileHandle);
for i := 0 to iBytesRead-1 do
begin
StringGrid1.RowCount := StringGrid1.RowCount + 1;
StringGrid1.Cells[1,i+1] := Buffer[i];
StringGrid1.Cells[2,i+1] := IntToStr(Integer(Buffer[i]));
end;
finally
FreeMem(Buffer);
end;
end;
end;
##FileOpen, FileSeek, FileRead Example

-----------------------------------------------------------------------------
FileWrite 写入档案
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function FileWrite(Handle: Integer; const Buffer; Count: Integer): Integer;
范例
procedure TForm1.Button1Click(Sender: TObject);
var
BackupName: string;
FileHandle: Integer;
StringLen: Integer;
X: Integer;
Y: Integer;
begin
if SaveDialog1.Execute then
begin
if FileExists(SaveDialog1.FileName) then
begin
BackupName := ExtractFileName(SaveDialog1.FileName);
BackupName := ChangeFileExt(BackupName, '.BAK');
if not RenameFile(SaveDialog1.FileName, BackupName) then
raise Exception.Create('Unable to create backup file.');
end;
FileHandle := FileCreate(SaveDialog1.FileName);
{ Write out the number of rows and columns in the grid. }
FileWrite(FileHandle,
StringGrid1.ColCount, SizeOf(StringGrid1.ColCount));
FileWrite(FileHandle,
StringGrid1.RowCount, SizeOf(StringGrid1.RowCount));
for X := 0 to StringGrid1.ColCount do
begin
for Y := 0 to StringGrid1.RowCount do
begin
{ Write out the length of each string, followed by the string itself. }
StringLen := Length(StringGrid1.Cells[X,Y]);
FileWrite(FileHandle, StringLen, SizeOf(StringLen));
FileWrite(FileHandle,
StringGrid1.Cells[X,Y], Length(StringGrid1.Cells[X,Y]);//?????????/
end;
end;
FileClose(FileHandle);
end;
end;
##FileExists, RenameFile, FileCreate, FileWrite, FileClose, ExtractFileName Example
-----------------------------------------------------------------------------
FileSeek 移动档案指标位置
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function FileSeek(Handle, Offset, Origin: Integer): Integer;
说明 Origin=0读/写指标由档案开头算起.
Origin=1读/写指标由目前位置算起.
Origin=2读/写指标移动到档案结束处.
**** 功能与Dos Int 21h 插断 42h 的功能相同.
失败传回-1.
范例 procedure TForm1.Button1Click(Sender: TObject);
var
FileHandle : Integer;
FileName : String;
Buffer : PChar;
S : String;
ReadBytes : Integer;
begin
FileName:='c:\delphi_test\abc.ttt';
S:='1234567890';
if FileExists(FileName) then
FileHandle := FileOpen(FileName, fmOpenReadWrite)
else
FileHandle := FileCreate(FileName);
if FileHandle < 0 then
Begin
MessageDlg('开档失败', mtInformation, [mbOk], 0);
Exit;
End;

GetMem(Buffer, 100);
try
StrPCopy(Buffer, S);
FileWrite(FileHandle,Buffer^,10);
FileSeek(FileHandle,4,0);
ReadBytes:=FileRead(FileHandle, Buffer^, 100);
Buffer[ReadBytes]:=#0;
Label1.Caption:=IntToStr(ReadBytes)+' '+
StrPas(Buffer);
finally
FreeMem(Buffer);
end;

FileClose(FileHandle);
end;

结果 存档後abc.ttt共有1234567890等十个Bytes.
从第五位元开始读取,共读取六个位元.
567890
(位移是从0开始算起)

procedure TForm1.Button1Click(Sender: TObject);

var
iFileHandle: Integer;
iFileLength: Integer;
iBytesRead: Integer;
Buffer: PChar;
i: Integer
begin
if OpenDialog1.Execute then
begin
try
iFileHandle := FileOpen(OpenDialog1.FileName, fmOpenRead);
iFileLength := FileSeek(iFileHandle,0,2);
FileSeek(iFileHandle,0,0);
Buffer := PChar(AllocMem(iFileLength + 1));
iBytesRead = FileRead(iFileHandle, Buffer, iFileLength);
FileClose(iFileHandle);
for i := 0 to iBytesRead-1 do
begin
StringGrid1.RowCount := StringGrid1.RowCount + 1;
StringGrid1.Cells[1,i+1] := Buffer[i];
StringGrid1.Cells[2,i+1] := IntToStr(Integer(Buffer[i]));
end;
finally
FreeMem(Buffer);
end;
end;
end;
##FileOpen, FileSeek, FileRead Example
-----------------------------------------------------------------------------
FileGetAttr 档案属性
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function FileGetAttr(const FileName: string): Integer;
说明 faReadOnly = $00000001;
faHidden = $00000002;
faSysFile = $00000004;
faVolumeID = $00000008;
faDirectory = $00000010;
faArchive = $00000020;
faAnyFile = $0000003F;
范例 procedure TForm1.Button1Click(Sender: TObject);
var
S: String;
begin
S:=IntToStr(FileGetAttr('c:\delphi_d\delphi_help1.txt'));
Label1.Caption := S;
end;
-----------------------------------------------------------------------------
FileSetAttr 设定档案属性
-----------------------------------------------------------------------------
Unit SysUtils
函数原型 function FileSetAttr(const FileName: string; Attr: Integer):
Integer;
说明 设定成功传回0

-----------------------------------------------------------------------------
FindClose 结束FindFirst/FindNext
-----------------------------------------------------------------------------
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;

if FindFirst(Edit1.Text, FileAttrs, sr) = 0 then

begin
with StringGrid1 do
begin
if (sr.Attr and FileAttrs) = sr.Attr then
begin

Cells[1,RowCount-1] := sr.Name;
Cells[2,RowCount-1] := IntToStr(sr.Size);
end;
while FindNext(sr) = 0 do
begin
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;
end;
FindClose(sr);
end;
end;
end;
##FindFirst, FindNext, FindClose Example
-----------------------------------------------------------------------------
FindFirst 寻找第一个符合的档案.
-----------------------------------------------------------------------------
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;

if FindFirst(Edit1.Text, FileAttrs, sr) = 0 then

begin
with StringGrid1 do
begin
if (sr.Attr and FileAttrs) = sr.Attr then
begin
Cells[1,RowCount-1] := sr.Name;
Cells[2,RowCount-1] := IntToStr(sr.Size);
end;
while FindNext(sr) = 0 do
begin
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;
end;
FindClose(sr);
end;
end;
end;
##FindFirst, FindNext, FindClose Example