Pascal edit, delete data in text file

[cubicbox]

Hi everyone, I'm now nearly finished with my project which tells us to write a PASCAL program for entering the information of the employees. However, I came across a BIG problem is that I've got no idea on how to edit records in the text files or delete unwanted data from the text file.
I've thought of:
- copying the data in the text file to an array
- complete the wanted operations in the array
- copy the data in the array back to the text file made blank by 'rewrite'

but I really have NO idea on how to edit or delete records...
the array that is used to store data in the text file now is a 2-D array.
would somebody please please please give me a clue on how to edit, delete data ?? I really need this to pass the term... so, please, please, please...

thanks in advance.

[finalist]

There is in Delphi a type of data TStringList ....
It is very easy to manage a text file using an instance of TStringList ....
But I don't know about Pascal supports TStringList or not ?

[FlamingClaw]

http://www.daniweb.com/code/forum124.html

[cubicbox]

um.. thanks both of you for your help. but then, still, I'm unable to find a solution to the problem.. maybe I'm a bit to redundant in defining the problem in my first post here. to simplify that, I've already copied data from text file into a 2-D array..
but I don't know how to edit , delete data in the array.. is there some kind of method?
thanks a lot.

[FlamingClaw]

hi :D

program something;
uses crt;
type rec = record
                 line:string;
           end;
     
     trec = array[1..3,1..3]of rec;

var t:trec;
    temp:array[1..9]of rec;
    f:file of rec;
    one:rec;
    i,j:byte;
    s:string;

procedure filefill;
begin
      assign(f,'recs.dat');
      {$I-}
      rewrite(f);
      {$I+}
      if ioresult <> 0 then begin
         writeln('file rewrite error');
         readln;
         halt;
      end;
      writeln('contents of the file: ');
      temp[1].line:='turbo';
      temp[2].line:='pascal';
      temp[3].line:='is';
      temp[4].line:='my';
      temp[5].line:='favorit';
      temp[6].line:='language';
      temp[7].line:='and';
      temp[8].line:='I am a ';
      temp[9].line:='hungarian';

      (*fill the file first*)
      for i:=1 to 9 do begin
          write(f,temp[i]);
          writeln(i,'. element: ',temp[i].line);
      end;
      writeln('file size: ',filesize(f));
      close(f);
      writeln('==========');
end;

procedure readback;
begin
      (*read it back*)
      assign(f,'recs.dat');
      {$I-}
      reset(f);
      {$I+}
      if ioresult <> 0 then begin
         writeln('file reset error');
         readln;
         halt;
      end;

      while not eof(f) do begin
            for i:=1 to 3 do begin
                for j:=1 to 3 do begin
                    read(f,t[i,j]);
                end;
            end;
      end;
      close(f);
end;


procedure writeout(x:trec);
var i,j:byte;
begin
     writeln('==========');
     for i:=1 to 3 do begin
         for j:=1 to 3 do begin
             write('t[',i,',',j,'].element:=',x[i,j].line);
             writeln;
         end;
     end;
end;

procedure modify(x:rec);
begin
     writeln('==========');
     writeln('give me the new string: ');
     readln(x.line);
     t[i,j]:=x;
end;


begin (*main*)

      clrscr;

      filefill;
      readback;
      writeout(t);
      writeln('==========');
      write('give me the first number of the matrix,max 1..3 : ');
      readln(i);
      write('and the second number ,max 1..3 : ');
      readln(j);

      if (i in [1,2,3]) and (j in [1,2,3]) then begin
          writeln('t[',i,',',j,']:=',t[i,j].line);
          modify(one);
          writeln('press enter to read the matrix again');
          readln;
          writeout(t);
      end else writeln('wrong index number entered');

      while not keypressed do continue;
end.
(*created by FlamingClaw 2010.02.17,Hungary*)

[cubicbox]

omg thank you so much FlamingClaw !
well.. by the way do you have any idea if I enter blank spaces in the program above (indicating I want to delete the data), it can automatically move everything up one line so that the program will not have blank lines in the middle? will I be able to do that?
thanks !!

[Jaxneo]

FlamingClaw, I have several output files (*.out) contain a lot of information. I would like to have a program can just sort specific data from each output file and save as the same filename with txt extension.

While reading each line (from *.out) if you are on a line that says "state summary:" then save next 10 lines (into *.txt). Please advise. Thanks!

[CikMuda]

hai.. please anyone help me to solve this code??actually i wanna know how do you update the data into the pascal code. in this case, I want to update data on the movie title. user can update each time the movie title on the latest movie out.below are my pascal coding :

Program RoyalCinema;
uses crt;

type
movie = char ;
AdultRecord = Record
AdmovieTitle : char;
AdmovieSession : movie;
AdmovieTime : real;
AdmovieSeat : movie;
AdmovieHall, Adpeople : integer;
End;

type smovie = char;
StudentRecord = Record
StmovieTitle : char;
StmovieSession : smovie;
StmovieTime : real;
StmovieSeat : smovie;
StmovieHall, Stpeople : integer;
End;

Var
AdmovieArray : Array [1..2] of AdultRecord;
StmovieArray : Array [1..2] of StudentRecord;
i : 1..10;
chooseCust,countA,countB, j, k : integer;
continue,update : String;
total,tot,payAdult,payStud : real;
search : char;

Procedure displayMENU( );
begin
writeln(' WELCOME TO OUR CINEMA ');
writeln;
readln;
writeln('*******************************************************************');
writeln('* HALL 1 *');
writeln('* [1] Darkest Hour *new [2] Sumpahan Kum Kum *new *');
writeln('* *');
writeln('* HALL 2 *');
writeln('* [3] Journey 2 [4] Suatu Malam Kubur Berasap *');
writeln('* *');
writeln('* HALL 3 *');
writeln('* [5] Underworld *new [6] Hantu Dalam Botol Kicap *');
writeln('* *');
writeln('* *');
writeln('* Session Available : *');
writeln('* *');
writeln('* [1] Day or Night *');
writeln('* [2] Midnight *');
writeln('* *');
writeln('* *');
writeln('* Seat Available : *');
writeln('* *');
writeln('* [1] Normal Seat *');
writeln('* [2] Couple Seat *');
writeln('* *');
writeln('* *');
writeln('*******************************************************************');
end;

procedure readCustDetails (var AdCinema : AdultRecord);
begin
writeln;

writeln('MOVIE : ');
read(AdCinema.AdmovieTitle);
writeln;
writeln('SESSION : ');
read(AdCinema.AdmovieSession);
writeln;
writeln('SHOW TIME : ');
read(AdCinema.AdmovieTime);
writeln;
writeln('CHOOSE THE TYPE OF SEAT');
read(AdCinema.AdmovieSeat);
writeln;
writeln('QUANTITY : ');
read(AdCinema.Adpeople);
writeln;
end;

procedure readStudDetails (var StCinema : StudentRecord);
begin
writeln;

writeln('MOVIE : ');
read(StCinema.StmovieTitle);
writeln;
writeln('SESSION : ');
read(StCinema.StmovieSession);
writeln;
writeln('SHOW TIME : ');
read(StCinema.StmovieTime);
writeln;
writeln('CHOOSE THE TYPE OF SEAT');
read(StCinema.StmovieSeat);
writeln;
writeln('QUANTITY : ');
read(StCinema.Stpeople);
writeln;
end;

Procedure displayAdult(var AdCinema : AdultRecord);
begin
writeln('Movie :: ', AdCinema.AdmovieTitle);
writeln('Session :: ', AdCinema.AdmovieSession);
writeln('Seat :: ', AdCinema.AdmovieSeat);
writeln(' ');
end;

Procedure displayStudent(var StCinema : StudentRecord);
begin
writeln('Movie :: ', StCinema.StmovieTitle);
writeln('Session :: ', StCinema.StmovieSession);
writeln('Seat :: ', StCinema.StmovieSeat);
writeln(' ');
end;

Function ADULTmoviePayment(Adpeople : integer ; AdmovieSeat : movie ; AdmovieSession : movie):real;
begin
total := 0;

if AdmovieSession = '1' then
begin
if AdmovieSeat = '1' then
total := (8.00 + 2.00) * Adpeople
else
begin
if AdmovieSeat = '2' then
total := (8.00 + 4.00) * Adpeople
end
end

else
begin
if AdmovieSession = '2' then
begin
if AdmovieSeat = '1' then
total := (8.00 + 2.00 + 3.00) * Adpeople
else
begin
if AdmovieSeat = '2' then
total := (8.00 + 4.00 + 3.00) * Adpeople
{else
begin
if AdmovieSeat = '3' then
total := (8.00 + 3.00) * Adpeople;
end;}
end;
end;
end;
ADULTmoviePayment := total;
end;

Function STUDmoviePayment(Speople : integer ; SmovieSeat : smovie ; SmovieSession : smovie):real;
begin
tot := 0;
if SmovieSession = '1' then
begin
if SmovieSeat = '1' then
tot := (8.00 + 2.00) * Speople - 0.30
else
begin
if SmovieSeat = '2' then
tot := (8.00 + 4.00) * Speople - 0.30
end
end

else
begin
if SmovieSession = '2' then
begin
if SmovieSeat = '1' then
tot := (8.00 + 2.00 + 3.00) * Speople - 0.30
else
begin
if SmovieSeat = '2' then
tot := (8.00 + 4.00 + 3.00) * Speople - 0.30
{else
begin
if AdmovieSeat = '3' then
total := (8.00 + 3.00) * Adpeople;
end;}
end;
end;
end;
STUDmoviePayment := tot;
end;

Procedure FindAdult(var AdCinema : AdultRecord; m : char);
begin
if (AdCinema.AdmovieSession = m) then
writeln('MOVIE : ',AdCinema.AdmovieTitle);
end;

Procedure FindStud(var StCinema : StudentRecord; n : char);
begin
if (StCinema.StmovieSession = n) then
writeln('MOVIE : ',StCinema.StmovieTitle);
end;

Procedure UpdateAdult(var AdCinema : AdultRecord; s : String);
begin
if AdCinema.AdmovieTitle = s then
begin
AdCinema.AdmovieTitle := ' ';
end
end;

Procedure UpdateStud(var StCinema : StudentRecord; k : String);
begin
if StCinema.StmovieTitle = k then
begin
StCinema.StmovieTitle := ' ';
end
end;

begin
clrscr;

writeln('******************* ROYAL CINEMA CUSTOMER SERVICE *********************');
writeln;
displayMENU();

continue := 'true';
j := 1;
k := 1;
countA := 0;
countB := 0;
if continue = 'yes' then
begin

writeln;
writeln('PLEASE CHOOSE THE TYPE OF CUSTOMER BASED ON THESE FOLLOWING CODE : ');
writeln;
writeln(' [1] Normal [2] Student ');
writeln;
writeln('--------------------------------------------------------------------');
writeln;
readln(chooseCust);
if chooseCust = 1 then
begin
{countA := countA + 1;}
for i := 1 to 2 do
begin
readCustDetails(AdmovieArray[countA]);
end;
end
else if chooseCust = 2 then
begin
{countB := countB + 1;}
for i := 1 to 2 do
begin
readStudDetails(StmovieArray[countB]);
end;
end;
writeln;
readln();
end;

clrscr;
writeln('LIST OF NORMAL CUSTOMER : ');
writeln('--------------------------------------------------------------------');
writeln('');
for i := 1 to 2 do
begin
displayAdult(AdmovieArray[i]);
{payAdult := ADULTmoviePayment(AdmovieArray[i]);
writeln('The Total Payment (RM) : ',payAdult:2:2);}
end;
writeln;

clrscr;
writeln('LIST OF STUDENT CUSTOMER : ');
writeln('--------------------------------------------------------------------');
writeln('');
for i := 1 to 2 do
begin
displayStudent(StmovieArray[i]);
{payStud := STUDmoviePayment(StmovieArray[i]);

writeln('The Total Payment (RM) : ',payStud:2:2);}
end;
writeln;

clrscr;
writeln;
writeln('PLEASE ENTER THE SESSION THAT YOU WANT TO SEARCH : ');
readln(search);
writeln('--------------------------------------------------------------------');

for i := 1 to 2 do
begin
writeln;
FindAdult(AdmovieArray[i],search);
readln;
writeln;
writeln;
FindStud(StmovieArray[i],search);
readln;
end;

clrscr;
writeln;
writeln('PLEASE ENTER THE MOVIE TITLE THAT YOU WANT TO UPDATE : ');
readln(update);
writeln('--------------------------------------------------------------------');

for i := 1 to 2 do
begin
writeln;
UpdateAdult(AdmovieArray[i],update);
readln;
writeln;
writeln;
UpdateStud(StmovieArray[i],update);
readln;
end;
writeln('Movie has been succesfully updated');

writeln;
writeln('Do you wish to continue? (yes/no)');
readln(continue);
end.

[pritaeas]

Start a new thread for this, instead of hijacking an old one, and please use code tags. Do not forget to post your error too.