Replacing text in a message with an HMTL snippet

[EagleNick]

Originally Posted by Lynne

I never use replacement variables if I only want to replace things in the post text. Replacement variables affect things *everywhere* and sometimes that screws things up big time.

Does the str_replace only replace exact matches like replacement variables do?
For example, if I set up a str_replace to replace "The Black Cat" with "The White Cat" will it also replace instances of just "cat" or just "white" to "the white cat"?