1. PHP-language, files Jouni Juntunen Oulu University of Applied Sciences
School of Business and Information Management

2. Why files? To store data Simple to use No database available
When storing complex data - use database

3. Basic steps using files from application
Open file
(Lock file while reading)
Read/write to/from file
(Release locking)
Close file

4. Opening file
Usually it is wise that applications don’t create file (necessary files are created manually during application setup)
Files must be NEVER stored under public_html

5. fopen() Opening modes r=read w=write a=append
$filehandle=fopen(”../somefile.csv”,”w”); …
Opening modes
r=read
w=write
a=append
Check for more modes on PHP-manual

6. fwrite()
$filehandle=fopen(”../somefile.csv”,”w”); flock($filehandle,LOCK_EX)) fwrite($filehandle,”Content to be added to file.”); flock($filehandle,LOCK_UN); Fclose($filehandle);

7. Reading a file
<?php $filehandle=fopen(”…/..data.csv”,”r”); while (!feof($filehandle)) //Check if we have reached end of file { $row($filehandle, 1024); //Read current row from file print ”$row<br>”; //Print row without any formatting } fclose($filehandle); ?>

8. fclose() You’ll have to ALWAYS remember to close to used file!
$filehandle=fopen(”../somefile.csv”,”r”);
fclose($filehandle);
You’ll have to ALWAYS remember to close to used file!

9. Using files in Applications
Data is stored to file using e.g. delimeter character
For example csv-file (Comma separated value)

10. Exercise
Implement simple guestbook which stores messages to csv-file