How Can I Create a Secure Password Regex with Minimum Length, Upper/Lowercase, Numbers, Special Characters, and Excluded Strings?

Regular Expression for Password with Enhanced Security

To ensure robust password security, a comprehensive regular expression is essential. It should adhere to the following criteria:

• Minimum Eight Characters: The password must contain at least eight characters.
• Uppercase and Lowercase Letters: It should include both uppercase and lowercase letters.
• Number and Special Character: Additionally, it must have at least one number and one special character from $#?!.
• Exclusion: Certain strings, such as "old password", "password", and "websitename", should not be included.

Here's an improved regular expression that meets these requirements:

^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)(?=.*[$#?!])[^old password|password|websitename]{8,}$

This expression ensures that the password:

• Has a minimum length of eight characters.
• Contains at least one uppercase letter, one lowercase letter, one number, and one special character.
• Excludes specific prohibited strings.

By implementing this regular expression, you can enhance the security of your password validation process and protect against common password weaknesses.

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