Javascript Diff Algorithm

By John Resig
2006-08-22


Javascript Diff Algorithm

Using an idea grabbed from a mailing list post, I implemented the diff algorithm discussed in the following paper (free registration required):

P. Heckel, A technique for isolating differences between files
Comm. ACM, 21, (4), 264--268 (1978).

The implementation, itself, has two functions, one of which is recommended for use:

diffString( String oldFile, String newFile )

This method takes two strings and calculates the differences in each. The final result is the 'newFile' marked up with HTML (to signify both deletions from the oldFile and additions to the newFile).

Sample Code

Sample Output

The red brown spotted fox jumped leaped over the rolling log.

Projects Using this Code:

• Wikipedia Animate
• AniWiki

Downloads

• jsdiff.js

Tutorial Pages:
» Javascript Diff Algorithm

Related Tutorials: » JavaScript Debugging Techniques with Firebug » Striped Tables Using JavaScript » Opening PDFs in a New Window with JavaScript » Essential Javascript -- A Javascript Tutorial » Submit Forms Conditionally using JavaScript » How to Setup a Randomising Function