Many programs have a search and replace function that allows you to replace text in the file you are currently editing. However, search and replace utilities allow you to replace text across multiple files or folders.
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The most powerful free program in this class is Replace Text (formerly BK ReplaceEm). It will carry out replacements in individual files, in a group of selected files, in a set of files determined by a file mask, or indeed every file in a folder.
Replacement can be by text string or by using regular expressions. You can even replace text within a nominated range such as html tags. The interface is both logical and powerful, but it does take a little getting used to, so read the Help file before using. Power users need look no further than this product.
A little less powerful, but a tad easier for normal users is A.F.9. It allows multiple search and replace operations in the one pass, can save search and replace operations for later re-use, and has full drag and drop support.
These programs are designed for use on text based files such as .txt and .html and must not be used on binary files or proprietary formats such as Microsoft Word.
If you want to search and replace these file types, then check out InfoRapid Search & Replace. It's not as powerful as the best binary editors, but with suitable add-ins it can handle certain Microsoft Office file types plus .rtf and .pdf
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InfoRapid Seach & Replace
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