1. Use Online Syntax highlighter services:
Before posting the code, get the highlighted html code from the following online services and paste it in blogger post in edit HTML mode where you want.
http://www.tohtml.com:
http://www.neathighlighter.com/
http://puzzleware.net/CodeHtmler/default.aspx
http://www.chami.com/colorizer
http://quickhighlighter.com/
2. For Windows Live Writer:
If you are using windows live writer, you can use following plugins and publish post.
http://www.codeplex.com/wlwSyntaxHighlighter
http://precode.codeplex.com/
http://sourcecodeplugin.codeplex.com/
3. SyntaxHighlighter:
It is the most popular javascript based highlighter. It has support for 3rd party applications like Blogger, WordPress, Joomla & many others.
See following to use it in blog:
http://urenjoy.blogspot.com/2008/10/publish-source-code-in-blogger.html
http://geektalkin.blogspot.com/2009/11/embed-code-syntax-highlighting-in-blog.html
4. Google Code Prettify:
The main drawback of syntax highlighter is loading time. It is not quick. So, google code prettify is an alternate option:
http://google-code-prettify.googlecode.com/svn/trunk/README.html
http://stackoverflow.com/questions/1852537/how-to-use-prettify-with-blogger-blogspot