We will add (?i) for matching a specific portion of a string in case insensitive way. Let’s see an example –We have one string below…

(?=) is used to check if a string (which we want to match) is followed by another string or not.(?<=) is used to check if…

Lets see with an example : We want to search a string “final” which must be preceded by “semi“. Here is two strings below:finalsemifinal Regex…

Lets see through example. We have two strings below ,Out First is Hello World. How is it?Out First is Hi World. How is it?I want…

We can explain our regular expression within the expression using comments. Syntax:(?#Commented Code) Suppose we have a two strings below:Hello worldhello World Regex to match…

Suppose we want to search the word Hello for only two times side by side in a line and we write a regex (?:Hello){2} Now…

When we search a pattern one or more time we use ‘*’. But Sometime we want to search a character or a pattern for a…

(?<!…) is used to checks if any preceding character or pattern does not match the specified pattern.Syntax: (?<!preceedingPattern)patternLet’s see with example: We have some lines…

Suppose we have some lines below from where we just want to cut out ‘hello’ regardless of its case.Lines: fetch hello onlynot hello-worldavailable hellonot the…