SemGeshiCodeFix presents clear, highlighted code on your blog and even works in comments.
- Download SemGeshiCodeFix plugin.
- Unzip and extract to a local folder.
- Upload extracted folder to wp-content/plugins folder.
- Go to plugins tab in WordPress admin panel and activate the plugin.
To show line numbers, use following code:
That is not in the plugin but you can put it in sem-code-fix.php after:
SemGeshiCodeFix, Plugin, WordPress Plugin, Geshi, Comments, Posts, Syntax Highlighter
Source:? Plugins Page