php check file diff exist and get file diff

Question

How can I check and find differences(e.g svn diff, netbeans diff) between two files using php?

Platform : Win 7 32bit, PHP 5.4.7 (VC9 X86 32bit thread safe), XAMPP Version 1.8.1

Loaded extensions : Core, bcmath, calendar, ctype, date, ereg, filter, ftp, hash, iconv, json, mcrypt, SPL, odbc, pcre, Reflection, session, standard, mysqlnd, tokenizer, zip, zlib, libxml, dom, PDO, bz2, SimpleXML, wddx, xml, xmlreader, xmlwriter, apache2handler, Phar, curl, mbstring, exif, gd, gettext, mysql, mysqli, pdo_mysql, pdo_sqlite, soap, sockets, sqlite3, xmlrpc, xsl, mhash

use, file() function, compare lines, highlight different parts. P.S.: Have you tried anything? — BlitZ
@CORRUPT I didn't find any script I used meld found from this answer stackoverflow.com/questions/11895570/… I could have created by my self but for now I need quick solution — ARIF MAHMUD RANA

inquam inquam · Accepted Answer · 2013-05-14T06:24:50

This all depends on how you wish to compare the files. Are they text files or binary files etc. If we assume they are text files you have to decide if white spaces should be ignored etc. What you could do is open the two files to compare and go through them character by character and compare them. What it boils down to is to solve the Longest Common Sub-sequence problem. I would recommend you to start looking at algorithms for comparing like found here for example

http://en.wikipedia.org/wiki/Diff#Algorithm

Another approach would be to include patch (which can be found for Windows to) and run that in the background to find differences and build patch files (since my guess is that you want to find the differences and be able to store them and maybe apply them later?)

php check file diff exist and get file diff

2 Answers