This is a small cheat sheet that i personally use for regex to be used in PHP with the help of preg_match() function.
Escape character in regex in PHP
I personally prefer to use / (forward slash) as delimiter in preg_match(‘/regex/’, $subject). So, in this case, if we want to use an url which has forward slash we will use \ (backward slash) as an escape character.
will need to written in the following way:
In the above example you will see that we have used \ (backward slash) as an escape character in the regex.
Using a different delimiter in regex
You have the freedom to select your own delimiter which is a non-alphabetic character in the regular expression used in the preg_match() function. Let’s take the same example and use % as a delimiter. Now since /(forward slash ) is not used as a delimiter you do not have to escape them anymore.
This is how it will be written: