Way to do global replace on dir full of html files?

I need to replace a string in a whole dir full of htm files - is there a way to do this from a dos run window? or any other way for that matter?

 

Dreamweaver can do that in the Find & Replace box - do the current selection, current page, the whole folder or even whole site.

 

Thinking from a batch file perspective... Is the substring you want to replace at a specific location in each file name?

Example:
xxxxxxxStringToReplacexxxx.html
xxxxxxxStringToReplacexxxx.html
xxxxxxxStringToReplacexxxx.html

Is the string delimited by a specific character?

Example:
xxx-StringToReplace-xxx.html
xxxxxx-StringToReplace-.html
-StringToReplace-xxxxxx.html

...Or is it completely random?

Can you provide a few example file names?