This question already has an answer here:
C# Regex, Unrecognized escape sequence
(1 answer)
Closed 5 years ago.
I have the following regex which is working ok in https://regex101.com/ and so I want to use it in C# but I get the error Unrecognized escape sequence \_.
^https:\/\/github\.com\/([a-zA-Z\-0-9]+)\/([a-zA-Z\-\_]+)\/commit\/([a-fA-F0-9]{40}),(.*),([0-9]+),([0-9]+)$
in C# I do that:
string regex = #"^https:\/\/github\.com\/([a-zA-Z\-0-9]+)\/([a-zA-Z\-\_]+)\/commit\/([a-fA-F0-9]{40}),(.*),([0-9]+),([0-9]+)$";
and then want to do:
if (Regex.IsMatch(input, regex)) and so on. the error is here on that line.
I cant understand why I get the error in case I use #
You don't need to escape underscores in C# regular expressions. The error is coming from the regular expression parser.
You mentioned it is working OK on regex101.com. Maybe double check that it is dealing with underscores in the way you expect.
Related
This question already has answers here:
How do I make part of a regex match optional?
(2 answers)
Order of regular expression operator (..|.. ... ..|..)
(1 answer)
Closed 1 year ago.
I am trying to match a substring of "Number" or "Number(s)" in a string using a single Regex. However, I can get them to match individually, but not together.
Individually,
'Number' can match the word number
'Number[(]s[)]' can match Number(s).
However, if I put them together and do "Number|Number[(]s[)]" it is not matching for (s) of "Number(s)".
What I have tried:
1: Put \b boundary around the second string, doesn't work.
2: Use \ to escape, but C# yells at me for unrecognized escape sequence, so I opted out of this option
I know that I can use two regex to do what I want, but I wanted to understand what is wrong here and learn.
Number|Number[(]s[)] wont match Number(s) because it's first part "Number" matches it.
Try change the pattern part order: Number[(]s[)]|Number. This will try to match first with the string with parentheses and if it can't it will try the short form.
Also the pattern should be: Number\(s\)|Number
The unrecognized escape error message comes because if you want this pattern written as a string literal you must escape the backslash signs: "Number\\(s\\)|Number".
This question already has answers here:
Regex escape with \ or \\?
(5 answers)
Closed 2 years ago.
I tried to use regexes in C#
^(?=.*\d)(?=.*[a - z])(?=.*[A - Z])(?=.*[!##$%^*])(?=.*[a-zA-Z]).{6,20}$
but \d comes as an error if i put [0-9] instead it wont work as desired
This should check the string has a uppercase, lowercase, symbol and a number
You should use [0-9]. Probably it is more correct... \d will catch non-european digits like рен (it is a Devanagari digit).
For the reason:
you probably wrote:
var rx = new Regex("\d");
But in this way the \d is an escape sequence of the string instead of being a regex.
Write
var rx = new Regex(#"\d");
to deactivate the escape expansion of strings.
This question already has answers here:
Regex Match all characters between two strings
(16 answers)
Closed 5 years ago.
I'm trying to parse a text looking for data inside this pattern:
{{([^]+)}}
i.e. any sequence of characters between {{ and }} .
But, when I try to build a Regex object:
Regex _regex = new Regex("{{([^]+)}}", RegexOptions.Compiled);
I got this error:
analysis of "{{([^]+)}}" - Set of [] not terminated....
whatever it means...
Someone has an hint?
The purpose of [^...] is to negate character classes present in the specified list. After the ^ symbol, in order to define a correct regular expression, you should include a set of characters to exclude like, for example [^a]+ (this matches one or more characters that don't include the literal a).
The regex you are attempting to define is probably:
{{\s*([\w]+)\s*}}
Visit this link for trying a working demo.
This is because [^] is not a valid regex, because you need to specify at least one symbol that you wish to exclude.
In order to capture the string up to the closing }} change the expression to this:
{{((?:[^}]|}[^}])*)}}
Demo.
This question already has answers here:
Unrecognized escape sequence for path string containing backslashes
(5 answers)
Closed 7 years ago.
I'm trying to validate a password field using regex under the namespace System.Text.RegularExpressions but I'm getting three errors for
'Unrecognized escape sequence'.
When I double click on the errors it highlights the '-' in my expression for the character range but I don't know why this is wrong.
// password must contain one uppercase, one lowercase and one digit
Regex reg = new Regex("^(?=.*[!##$%^&*()\-_=+`~\[\]{}?|])(?=.+[a-z])(?=.+[A-Z])(? =.+[0-9]).{8,50}$");
Just add an # before the first quote to make it a verbatim string literal or escape the backslashes as \\.
it seems you have one space after ?
(? =.+[0-9]).{8,50}
remove that.
This question already has answers here:
Regex to pick characters outside of pair of quotes
(6 answers)
Closed 7 years ago.
I am new in writing regular expression and I have the following Scenario.
I have a string, like :
string line = "if (true){var data = string.Format(\"something {0} {1}.\", \"is\", \"wrong\");}";
now I need to write a regular expression that just pick the closing curly braces which are not in the double quote
so far I tried this:
"(^(\"[^\"]*\")(}))+"
^(\"[^\"]*\") : I want to Ignore any substring which is inside double quote, AND
(}) : I want to take }
+: for at least 1 occurrence.
But it seems I Did something wrong. Could any one please guide me to sort out where I did the wrong?
Thank you.
You just need these parts of your regex:
(?:\"[^\"]*\")|(})
Regex live here.