Regular expressions are used to find certain words or patterns inside of strings.
Regular expressions are usually surrounded by
For example, if we wanted to find the number of times the word the occurred in the string The dog chased the cat, we could use the following regular expression:
Let’s break this down a bit:
the is the pattern we want to match.
+means we want to find one or more occurrences of this pattern.
gmeans that we want to search the entire string for this pattern.
imeans that we want to ignore the case (uppercase or lowercase) when searching for the pattern.