How do you find the difference between two lines in PHP?

Question

I have 2 lines that I would like to compare, and return the positions of different characters in the second line.

For example, if I have

• "The brown fox jumps over the lazy dog"
• "The quick brown fox jumped over the lazy dog"

I want it to highlight "fast" and "ed". What is the best way to do this in PHP?

Answer 1

This can do the trick:

PHP Inline Diff

Text_diff

Answer 2

The algorithm you are looking for is "the longest common substring problem." From there it’s easy to spot the differences. See Wikipedia:

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

Answer 3

, , ! , str1 - " ", str2 - " ".

"lase Amy" "Amylase"?

- !