Regex forward slash

Question

What does a '/' character mean in a regular expression?

I have observed the following example to match single or double digit numbers.

/^\d{1,2}$/

When I googled multiple regex cheat sheets, the forward slash did not show up as a character with meaning in regex....

What does '/' do in regex?

It does not matter what language. These are regex delimiters. They are not part of the regex patterns, just separate regex action, pattern and modifiers. — Wiktor Stribiżew, May 27 '16 at 20:54
`/` is to regex as `"` is to strings. It's just the delimiter. — 4castle, May 27 '16 at 20:55
Possible duplicate of [Regular Expression meaning of a forward slash /](http://stackoverflow.com/questions/36439417/regular-expression-meaning-of-a-forward-slash) — Laurel, May 28 '16 at 00:48

gregmac · Answer 1 · 2016-05-27T21:00:19.353

It doesn't actually do anything. In Javascript, Perl and some other languages, it is used as a delimiter character explicitly for regular expressions.

Some languages like PHP use it as a delimiter inside a string, with additional options passed at the end, just like Javascript and Perl (in this case, "m" for multi-line):

 preg_match("/^\d{1,2}$/m", $input);

With this syntax, you can also use other characters, which can make matching literal /'s easier:

 preg_match("![a-z]+/[a-z]+!i", "Example/Match");

Regex forward slash

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