Regular Expression Password Validator

Question

I'm having a hard time trying to create a right regular expression for the RegularExpressionValidator control that allows password to be checked for the following: - Is greater than seven characters. - Contains at least one digit. - Contains at least one special (non-alphanumeric) character.

Cant seem to find any results out there too. Any help would be appreciated! Thanks!

Answer 1

Maybe you will find this article helpful. You may try the following expression

^.*(?=.{8,})(?=.*[\d])(?=.*[\W]).*$

and the breakdown:

• (?=.{8,}) - contains at least 8 characters
• (?=.*[\d]) - contains at least one digit
• (?=.*[\W]) - contains at least one special character

Answer 2

http://msdn.microsoft.com/en-us/library/ms972966.aspx

Search for "Lookaround processing" which is necessary in these examples. You can also test for a range of values by using .{4,8} as in Microsoft's example:

^(?=.*\d).{4,8}$

Answer 3

Try this

((?=.*\d)(?=.*[a-z])(?=.*[\W]).{6,20})

Description of above Regular Expression:

(           # Start of group
  (?=.*\d)      #   must contains one digit from 0-9
  (?=.*[a-z])       #   must contains one lowercase characters
  (?=.*[\W])        #   must contains at least one special character
              .     #     match anything with previous condition checking
                {7,20}  #        length at least 7 characters and maximum of 20 
)           # End of group

"/W" will increase the range of characters that can be used for password and pit can be more safe.

Answer 4

Use for Strong password with Uppercase, Lowercase, Numbers, Symbols & At least 8 Characters.

//Code for Validation with regular expression in ASP.Net core.
[RegularExpression(@"^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[^\da-zA-Z]).{8,15}$")]

Regular expression password validation:

@"^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[^\da-zA-Z]).{8,15}$"