Is there any way to find and replace text string automatically in all folder\'s files?
Press ctrlshiftF (cmdshiftF on Mac OS X :) and then put *.* in the where: field
This will open the search up to all files in the project as opposed to only open files or folders.
You can also use this to search only files of a certain type, or with a certain name regardless of type. It's just wildcards for the filename and extension.