Programming – Pascal: Essential skills 5

 

Learning Outcomes:

• Manipulate text files through filehandling statements.
• The manipulation involves file updating statements to delete, insert, append and amend records.
  
   

Text file handling

Read from file

var                 infile : text;         (* text file variable *)                 a : integer; begin                 assign (infile, ‘yourfile.txt’);         (* step 1: associate the file with the variable *)                 reset (infile);                                      (* step 2: read from beginning *)                 while not eof (infile) do                 begin                                 readln (infile, a);                (* step 3: read the integer and put into a *)                                 writeln (a)                           (* write the content on the screen *)                 end;                 close (infile)                                         (* step 4: close the file properly *) end;

 

Write into file

var                 infile : text;         (* text file variable *)                 a : integer; begin                 assign (infile, ‘yourfile.txt’);         (* step 1: associate the file with the variable *)                 rewrite (infile);                                 (* step 2: create or erase the file for writing*)                 a := 1;                 writeln (infile, a);                               (* step 3: put the integer into the file *)                 close (infile)                                         (* step 4: close the file properly *) end;

 

Relevant past paper:

DSE ICT Elect B(SP-2017):  PP 4cd. 2012 4aii.

CE CIT Elect A(2005-2011): 2005 2a. 2009 2abi. 2010 4a. 2011 4cd.