Adding instead of replacing items to a text file Delphi

Question

I made a simple program that adds ones information (Name, surname, ID ect) to a .txt file. When ever I make new details in the program, and click on a button to save the information, it rewrites it in the .txt file.

Here's my code:

procedure TForm1.BitBtn1Click(Sender: TObject);
var
  InfoFile                 : TStringList;
  Name, Surname, ExtraInfo : String;
  PhoneNumber,ID           : Integer;
  Date                     : TDateTime;
begin
  InfoFile := TStringList.Create;
  Name := edtName.text;
  Surname := edtSurname.Text;
  ID := StrToInt64(edtID.Text);
  PhoneNumber := StrToInt64(edtPhone.Text);
  Date := StrToDate(edtJoinDate.Text);

  try
    InfoFile.Add('NAME: '+Name);
    InfoFile.Add('SURNAME: '+Surname);
    InfoFile.Add('ID NUMBER: '+IntToStr(ID));
    InfoFile.Add('PHONE NUMBER: '+IntToStr(PhoneNumber));
    InfoFile.Add('DATE JOINED :'+DateToStr(Date));
    InfoFile.Add('');         // Spacers to separate next set of details
    InfoFile.Add('');

    InfoFile.SaveToFile('C:\Users\GrassMan\Desktop\InfoSaver\imfofile.txt');
  finally
    InfoFile.Free;
  end;

So instead of ADDING new details to the .txt file, its rewriting it. I know im doing something, if someone wouldn't mind giving me a hand.

Thanks

Answer 1

Should look like this:

begin
    InfoFile := TStringList.Create;
    Name := edtName.text;
    Surname := edtSurname.Text;
    ID := (edtID.Text);
    PhoneNumber :=(edtPhone.Text);
  try
    InfoFile.LoadFromFile('C:\Users\grassman\Desktop\infofile.txt');
    InfoFile.Add('NAME: '+Name);
    InfoFile.Add('SURNAME: '+Surname);
    InfoFile.Add('ID NUMBER: '+ ID);
    InfoFile.Add('PHONE NUMBER: '+(PhoneNumber));
    InfoFile.Add('Time of registration: ' + TimeToStr(time));
    InfoFile.Add('Date of registration: ' + DateToStr(date));
    InfoFile.Add('');         // Spacers to separate next set of details
    InfoFile.Add('');
    InfoFile.SaveToFile('C:\Users\grassman\Desktop\infofile.txt');
  finally
    InfoFile.Free;

Answer 2

Either load the file at the beginning (via LoadFromFile), before adding to it and writing it back; or else forget about TStringList, and just use WriteLn, after opening the file with Append.

Answer 3

procedure TForm1.BitBtn1Click(Sender: TObject);
var
  InfoFile                 : TStringList;
  Name, Surname, ExtraInfo : String;
  PhoneNumber,ID           : Integer;
  Date                     : TDateTime;
  FS                       : TFileStream;
begin
 Name := edtName.text;
  Surname := edtSurname.Text;
  ID := StrToInt64(edtID.Text);
  PhoneNumber := StrToInt64(edtPhone.Text);
  Date := StrToDate(edtJoinDate.Text);

  InfoFile := TStringList.Create;
  try
    InfoFile.Add('NAME: '+Name);
    InfoFile.Add('SURNAME: '+Surname);
    InfoFile.Add('ID NUMBER: '+IntToStr(ID));
    InfoFile.Add('PHONE NUMBER: '+IntToStr(PhoneNumber));
    InfoFile.Add('DATE JOINED :'+DateToStr(Date));
    InfoFile.Add('');         // Spacers to separate next set of details
    InfoFile.Add('');

    FS := TFileStream.Create('C:\Users\GrassMan\Desktop\InfoSaver\imfofile.txt', fmOpenWrite);
    try
      FS.Seek(0, soEnd);
      InfoFile.SaveToStream(FS);
    finally
      FS.Free;
    end;
  finally
    InfoFile.Free;
  end;
end;

Answer 4

You should use TFileStream:

var
  recordStr: string;
  fs: TFileStream;
  fsFlags: Word;
  filePath: string;
begin
  filePath := 'C:\Users\GrassMan\Desktop\InfoSaver\imfofile.txt';

  recordStr := 'NAME: '+ Name + #13#10 +
               'SURNAME: '+ Surname + #13#10 +
               'ID NUMBER: '+ IntToStr(ID) + #13#10 +
               'PHONE NUMBER: '+ IntToStr(PhoneNumber) + #13#10 +
               'DATE JOINED :' + DateToStr(Date) + #13#10 +
               #13#10#13#10; // Spaces to separate next set of details

  // open if exists, create if not
  fsFlags := fmOpenWrite;
  if (not FileExists(filePath)) then
    fsFlags := fsFlags or fmCreate;

  try
    fs := TFileStream.Create(filePath);
    try
      fs.Seek(0, soEnd); // go to the end of the file

      fs.Write(recordStr[1], Length(recordStr));
    finally
      fs.Free;
    end;
  except on ex: Exception do
    begin
      ShowMessage('Error while writing to the file: ' + ex.Message);
    end;
  end;
end;