密码的表达式正则

Question

I need the correct regular expression pattern, for checking input text in HTML matching this format:

• Start with a capital letter

• End with the character $

• Between the initial capital letter and the final dollar character there may be:

  1. Letter between a and z (both included) uppercase or lowercase
  2. Digit from zero to nine (two included)
  3. The underscore character ( _ )

Example: B4rc3l0nA$, Fr4_nc3$, A$

I think I have to add anchors at the beginning and at the end, but I don't know how to join everything so that the complete regular expression remains.

<input type="text" placeholder="Your password" pattern="^\[a-z]i\s-\s[0-9]{2}\([a-z]{1,3})$" required>

Answer 1

You can use this regular expression.

^[A-Z]\w+?\$$

1. ^[AZ] meaning start with capital character as first letter.
2. \w+? any letter or number or underscore
3. \$$ dollar sign at the end.

 const checkPassword = (password) => { return /^[AZ]\w+?\$$/.test(password) } console.log(checkPassword("B4rc3l0nA$")) console.log(checkPassword("Fr4_nc3$")) console.log(checkPassword("Fr4_nc3")) console.log(checkPassword("fr4_nc3$")) console.log(checkPassword("Ab!!@@ÅÆØ}$"))

FOR TESTING