Regular Expression: match whole line

I needed to match find a string within  multiple text files. I used this expression to do it. The line started with stringtomatch, but you could change to search within a line by prefixing .*

^stringtomatch.*$

^ – caret matches start of line

$ – dollar matches end of line

stringtomatch - string to match at the start of the line, if its in the middle you could prefix .* (i.e     .*stringtomatch.*    )

.* - matches any characters

Regular Expression: match whole line