If you use Linux you will always need a day to replace a string in multiple files without having to do everything manually.

Imagine that you want to replace an email address in all files. Php of a directory and its subdirectories. If the address is to replace adish@gmail.com and the new address is "adish1@yahoo.com", here is the command.

Code:
find. -name "*. php"-print | xargs sed-i 's / adish gmail.com/adish1 @ @ gmail.com / g'

Replace the *. php extension you want. And if you want to do it in all files (all extensions), you can also *.*