Split/merge files in delphi

// Split/merge files

{
Parameters:

FileToSplit: Specify a file to split.
SizeofFiles: Specify the size of the files you want to split to (in bytes)
Progressbar: Specify a TProgressBar to show the splitting progress

Result:
SplitFile() will create files FileName.001, FileName.002, FileName.003 and so on
that are SizeofFiles bytes in size.
}

function SplitFile(FileName : TFileName; SizeofFiles : Integer; ProgressBar : TProgressBar) : Boolean;
var
i : Word;
fs, sStream: TFileStream;
SplitFileName: String;
begin
ProgressBar.Position := 0;
fs := TFileStream.Create(FileName, fmOpenRead or fmShareDenyWrite);
try
for i := 1 to Trunc(fs.Size / SizeofFiles) + 1 do
begin
SplitFileName := ChangeFileExt(FileName, ‘.’+ FormatFloat(‘000’, i));
sStream := TFileStream.Create(SplitFileName, fmCreate or fmShareExclusive);
try
if fs.Size – fs.Position < SizeofFiles then
SizeofFiles := fs.Size – fs.Position;
sStream.CopyFrom(fs, SizeofFiles);
ProgressBar.Position := Round((fs.Position / fs.Size) * 100);
finally
sStream.Free;
end;
end;
finally
fs.Free;
end;

end;

// Combine files / Dateien zusammenführen

{
Parameters:

FileName: Specify the first piece of the splitted files
CombinedFileName: Specify the combined file name. (the output file)

Result:
CombineFiles() will create one large file from the pieces
}

function CombineFiles(FileName, CombinedFileName : TFileName) : Boolean;
var
i: integer;
fs, sStream: TFileStream;
filenameOrg: String;
begin
i := 1;
fs := TFileStream.Create(CombinedFileName, fmCreate or fmShareExclusive);
try
while FileExists(FileName) do
begin
sStream := TFileStream.Create(FileName, fmOpenRead or fmShareDenyWrite);
try
fs.CopyFrom(sStream, 0);
finally
sStream.Free;
end;
Inc(i);
FileName := ChangeFileExt(FileName, ‘.’+ FormatFloat(‘000’, i));
end;
finally
fs.Free;
end;
end;

// Examples:

procedure TForm1.Button1Click(Sender: TObject);
begin
SplitFile(‘C:\temp\FileToSplit.chm’,1000000, ProgressBar1);
end;

procedure TForm1.Button2Click(Sender: TObject);
begin
CombineFiles(‘C:\temp\FileToSplit.001′,’H:\temp\FileToSplit.chm’);
end;