split/merge files?

Author: Rainer Kümmerle

// Split file / File splitten

{

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;