Regex to validate string having only lower case, first char must be a letter

Question

I want to use the Regex to validate the string containing

• must contain only lower case letters
• first char must be a letter.
• remaining characters must match regex [a-z0-9_.]

I use the /^[\w\s\-.]*$/ to validate the string. But it allows the first character like (._)

Answer 1

Why don't you just stick to your requirements ?

• first char must be a lowercase letter: [a-z]
• remaining characters must match: [a-z0-9_.]

-> your regex: /^[a-z][a-z0-9_.]*$/