C# .NET Regex 'Unrecognized escape sequence'

Question

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}$");

Why have you specified a maximum length for the password? Please, never do that. — David Arno, Nov 23 '15 at 13:30
Duplicate talks about paths, but it's the same \ character/lack of @ causing the problem. — James Thorpe, Nov 23 '15 at 13:31
it seems `(? =.+[0-9]).{8,50}` here you have one space after `?` it should not be — Deepak Sharma, Nov 23 '15 at 13:31

score 5 · Answer 1 · answered Nov 23 '15 at 13:30

5

Just add an @ before the first quote to make it a verbatim string literal or escape the backslashes as \\.

answered Nov 23 '15 at 13:30

LegionMammal978

score -1 · Answer 2 · answered Nov 23 '15 at 13:32

-1

it seems you have one space after ?

(? =.+[0-9]).{8,50}

remove that.

answered Nov 23 '15 at 13:32

Deepak Sharma

2 Answers2