Is underscore special in regex?

Is underscore special in regex?

Regex doesn't recognize underscore as special character.

Do I need to escape underscore regex?

4 Answers. Just escape the dashes to prevent them from being interpreted (I don't think underscore needs escaping, but it can't hurt). You don't say which regex you are using. Also, you probably don't need the parentheses unless this is part of a larger expression.

What are alphanumerics and underscores?

In Computer Science, an Alphanumeric value often means the first character is not a number but is an alphabet or underscore. Thereafter the character can be 0-9 , A-Z , a-z , or underscore ( _ ).

What is Alnum in regex?

The [[:alnum:]] character class represents alphabetic and numeric characters, and it is same as using [a-zA-Z0-9] in regular expression.

Can we use underscore in password?

You can use any of the following characters in login names, passwords, and email addresses: Any letters from a to z: You can use uppercase letters to make the password and email address easier to remember. ... These special characters: @ (at sign) . (period) - (hyphen or dash) _ (underscore)

Is a regex character?

A regular expression (shortened as regex or regexp; also referred to as rational expression) is a sequence of characters that specifies a search pattern. Usually such patterns are used by string-searching algorithms for "find" or "find and replace" operations on strings, or for input validation.

What does underscore mean in regex?

The _ (underscore) character in the regular expression means that the zone name must have an underscore immediately following the alphanumeric string matched by the preceding brackets. The . (period) matches any character (a wildcard).

Are there regular expressions for uppercase and underscores?

I would like to have a regular expression that checks if a string contains only upper and lowercase letters, numbers, and underscores. To match a string that contains only those characters (or an empty string), try This works for .NET regular expressions, and probably a lot of other languages as well.

How to check regex for alphanumeric and underscore?

The following regex matches alphanumeric characters and underscore: The pattern in your code is correct, but the pattern above only checks a single instance. – BenAlabaster Dec 3 '08 at 4:35 That was intentional, code sample was intended as a clarifying usage in actually checking a string.

Do you know any regex that can return word that has been underlined?

You mean underline. I thought underscore. Sorry for the confusion. I gave regex if word contains underscore not underlined. Sorry I mixed up between underline and underscore! Do you know any Regex that able to return word that has been underlined in Words Document ?

Do you use upper or lower case alphanumeric or underscore?

Will do at least one upper or lower case alphanumeric or underscore. If it can be zero length, then just substitute the + for * If diacritics need to be included (such as cedilla - ç) then you would need to use the word character which does the same as the above, but includes the diacritic characters: