2Bytesprog2 course_2014_c4_binaryfiles
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This document provides instructions for a programming assignment on binary files. It defines a record type for books with fields for number, title, author, publication date, and borrowed status. It describes a program that reads book data from a text file into a binary file, allows the user to specify borrowed books by number, updates the borrowed field in the binary file, and outputs a list of borrowed books. It also shows how to access specific records in the binary file using seek and read the publication dates of the 5th and last books.
![Ex:
1. Type person=record
fname: string[20];
lname: string[25];
age: integer;
end;
Var f1 : file of person ;
2.Var f2: file of char ;
3.Type arr=array[1..100] of real;
Var f3: file of arr ;
Note : Binary files are similar to arrays but there are
Two different points …
A. Accessible to the element
B. Size ](https://image.slidesharecdn.com/2bytesprog2course2014c4binaryfiles-141203172904-conversion-gate01/85/2Bytesprog2-course_2014_c4_binaryfiles-5-320.jpg)
![Program 2_bytesprog
Uses wincrt
Type Date=record
day:1..31;
month:1..12;
year:1900..2013;
end;
Book=record
number : integer;
title,author: string[30];
pub_date : Data;
borrowed : Boolean;
end;
Var : f_text :text;
f_bin,temp :file of Book;
i,j,n : integer;
abook: book;
C: char; found: Boolean;
Borrowed_book : array of integer;](https://image.slidesharecdn.com/2bytesprog2course2014c4binaryfiles-141203172904-conversion-gate01/85/2Bytesprog2-course_2014_c4_binaryfiles-11-320.jpg)
![writeln('enter the total number of the lend books');
readln(n);
for i:=1 to n do
begin
writeln('enter the number of the book'); readln(Borrowed_book[i]);
end;
Assign(temp,’c:/myfile.bin)
reset(f_bin);
rewrite(temp);
While not eof(f_bin) do begin read(f_bin,abook); found:=false; i:=1; while i<=n and not found do begin if Borrowed_book[i]=abook.number then found:= true; i:=i+1; end; if found then abook.borrowed:=true; write(temp,abook); end;](https://image.slidesharecdn.com/2bytesprog2course2014c4binaryfiles-141203172904-conversion-gate01/85/2Bytesprog2-course_2014_c4_binaryfiles-13-320.jpg)
2Bytesprog2 course_2014_c4_binaryfiles
- 1. Prog_2 course- 2014 2 bytes team Kinan keshkeh IT Engineering-Damascus University 3rd year
- 2. Binary files
- 3. files are divided into : Binary files Text files 1.Definition 2.Assign 3.Initialize : 4.Operations : 5.Close Files Rewrite Reset append Write writeln Read Readln In the same way we define Binary files but there are some changes Let’s go ....
- 4. Binary file It is a type of files that has the same kind of elements and each element inside binary file has the same size ….. 1)Definition : var filename : file of <type>; • filename : name from user • file of : Two words are reserved • type : any type standard or structure ( char ,integer , string , array , record ……)
- 5. Ex: 1. Type person=record fname: string[20]; lname: string[25]; age: integer; end; Var f1 : file of person ; 2.Var f2: file of char ; 3.Type arr=array[1..100] of real; Var f3: file of arr ; Note : Binary files are similar to arrays but there are Two different points … A. Accessible to the element B. Size
- 6. fname lname age fname lname age fname lname age fname lname age ………. fname lname age 20 bytes 25 bytes 2 bytes { 47 bytes } Seek(f1,0) Seek(f1,filesize(f)) Seek(f1,2) Seek(f1,1)
- 7. 2)Assign : Assign(f1,’c:myfile.bin’); 3)Initialize : A.Rewrite(f) : Used when we want to write or adjustment on a binary file B.Reset(f) : Used when we want to read on a binary file 4)Operations : A.Write : access to data when we initialize binary file to write B.Read : access to data when we initialize binary file to read 5) close : to save changes or store data in binary file
- 8. Functions uses in binary files : 1.Seek(filename, i) : Used to move the cursor to element number (i) where counting starts from For example seek(f,5) 2.Eof(filename) :return true when file ends 3.Filesize(f) : return The number of elements in binary file Note : we use these functions only when initialize binary file to read Note : we don’t use eoln(f) in binary file because there are no lines zero
- 9. Lets make it real :D !!
- 10. hard Exercise public (8) أكتة تر اَيجا يقىو تانع هًياخ انتانيح : .1 انخز في يهف ث اُئي ن عًطياخ تعريف انكتة في يكتثح , يىصف انكتاب ترقى تسهسهي , وع ىُا , واسى ان ؤًنف , وتاريخ الإصذار , إضافح إنى حقم ي طُقي يذل عهى الإعارج....يقىو انثر اَيج تقراءج ان عًطياخ ي يهف صَي. .2 تسجيم الإعارج أو الإعادج في ان هًف, يقىو ان سًتخذو تئعطاء جذول تأرقاو انكتة ان عًارج وان عًادج , نيسجهها انثر اَيج عهى ان هًف. . 3 إظهار لائحح تانكتة ان عًارج. .4 طهة إضافي : طثاعح تاريخ إصذار انكتاب انخايس وانكتاب الأخير في ان هًف انث اُئي
- 11. Program 2_bytesprog Uses wincrt Type Date=record day:1..31; month:1..12; year:1900..2013; end; Book=record number : integer; title,author: string[30]; pub_date : Data; borrowed : Boolean; end; Var : f_text :text; f_bin,temp :file of Book; i,j,n : integer; abook: book; C: char; found: Boolean; Borrowed_book : array of integer;
- 12. Begin assign(f_text ,’c:text.txt’); assign(f_bin ,’c:binary.bin’); reset(f_text); rewrite(f_bin); while not eof(f_text) do begin with abook do begin readln(f_text,number,author,title,pub_date.day,c, pub_date.month,c,pub_date.year,c); if c='y' then borrowed:=true; if c='n' then borrowed:=false; end; {with} write(f_bin,abook); end; {while} close(f_text); close(f_bin); +1 +2
- 13. writeln('enter the total number of the lend books'); readln(n); for i:=1 to n do begin writeln('enter the number of the book'); readln(Borrowed_book[i]); end; Assign(temp,’c:/myfile.bin) reset(f_bin); rewrite(temp); While not eof(f_bin) do begin read(f_bin,abook); found:=false; i:=1; while i<=n and not found do begin if Borrowed_book[i]=abook.number then found:= true; i:=i+1; end; if found then abook.borrowed:=true; write(temp,abook); end;
- 14. close(f_bin); close(temp); Reset(temp); rewrite(f_bin); while not eof(temp) do begin read(temp,abook); write(f_bin,abook); end; close(temp); close(f_bin); rewrite(temp); close(temp);
- 15. Reset(f_bin); While not eof(f_bin) do begin Read(f_bin,abook); If (abook.borrowed) then Writeln(abook.number,’ ‘ ,abook.title); end; Seek(f_bin,4); Read(f,abook); Writeln(‘the book number five has appeared in : ‘,abook.day, ‘ ‘ ,abook.month, ‘ ‘ ,abook.year); Seek(f_bin,filesize(f_bin)); Read(f,abook); Writeln(‘the last book has appeared in : ‘,abook.day, ‘ ‘ ,abook.month, ‘ ‘ ,abook.year); End.
- 16. Homework: لذ ىٌا ملفان ثىائ اٍن مه الاعذاد الصح حٍة مزتبة تصاعذ اٌ وز ذٌ دمجهما بح ثٍ وحصل على ملف واحذ مزتب حٌىي عىاصز الملف هٍ سىقىم بالذمج دون استخذام الجذاول ف البزوامج لأوىا وفتزض أن الملفان كب زٍان جذا و هذا ما وسم هٍ بالفزس الخارج . 1 أكتب أولا بزوامجا ىٌشئ الملفات الثىائ ةٍ مه ملفات وص ةٍ تحىي أعذاد صح حٍة . 2 أكتب بزوامج الذمج الذي ىٌشئ الملف الثىائ الىاتج . 3 أكتب الملف الثىائ الىاتج مجذدا ف ملف وص Good luck…..
- 17. Group : group link Mobile phone- Kinan : 0994385748 Facebook account : kinan’s account 2 bytes team