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Language: Pascal
Expertise: Beginner

Jan 29, 1999

Question:
I want to split a TXT file into smaller TXT files. The program should split the file every time there are three empty lines. For example:

Paragraph1



Paragraph2

Paragraph1 and Paragraph 2 would become separate text files. I would be grateful if you could tell me which commands I should use or even build such program if it isn't too difficult.

Answer:
That's an interesting problem. Assuming that you won't ever need to go back to an original file, you can use the same file variable to handle all the destination files. It's just a matter of counting. Here's wrapper procedure that ought to work.

procedure CreateABunchOfFiles(SourceFile : String);
var
  fSource,
  fDest       : TextFile;
  buf         : String;
  BlankCounter,
  DestCounter : Integer;
begin
  //Let's initialize the variables
  DestCounter := 1;
  BlankCounter := 1;
  AssignFile(fSource, SourceFile);
  Reset(fSource);
  AssignFile(fDest, 'Dest' + IntToStr(DestCounter) + '.TXT');
  Rewrite(fDest);
  //Now go through the file line by line
  while NOT EOF(fSource) do begin
    ReadLn(fSource, buf);
    //Make sure we remove all trailing and leading spaces
    //to catch blank lines. If we come across a blank line,
    //then skip the rest of processing and move to the next
    //one. This is ultra important because some text files'
    //blank lines contain spaces or null characters, they'll
    //be read as real bytes.

    if (TrimLeft(TrimRight(buf)) = '') then
        Inc(BlankCounter);
    else
      //Okay, we've come across three blank lines in a row
      if (BlankCounter = 3) then
        begin
          //Reset the counter
          BlankCounter := 1;
          //Close current destination file
          CloseFile(fDest);
          //Increment the Destination File ID (DestCounter)
          Inc(DestCounter);
          //Open up a new file based on the new name
          AssignFile(fDest, 'Dest' + IntToStr(DestCounter) +
'.TXT');
          Rewrite(fDest);
        end
      else
        //Otherwise, just write the line to the current
destination
        WriteLn(fDest, buf);
  end;
end;

This solution is pretty straightforward File I/O stuff, so I won't go into detail here. Look over the logic to understand how it works. I commented it pretty well so you can follow it easily.