Regular Expressions Challenge 2

Restrict Possible Usernames(Challenge)

• Usernames are used everywhere on the internet. They are what give users a unique identity on their favorite sites.

• You need to check all the usernames in a database. Here are some simple rules that users have to follow when creating their username.

• Usernames can only use alpha-numeric characters.

• The only numbers in the username have to be at the end. There can be zero or more of them at the end. Username cannot start with the number.

• Username letters can be lowercase and uppercase.

• Usernames have to be at least two characters long. A two-character username can only use alphabet letters as characters.

• Change the regex userCheck to fit the constraints listed above.
  

let username = "JackOfAllTrades";
let userCheck = /^[a-z][a-z]+\d*$|^[a-z]\d\d+$/i; 
let result = userCheck.test(username);

• Code Explnantion: Code Explanation
• ^ - start of input
• [a-z] - first character is a letter
• [a-z]+ - following characters are letters
• \d*$ - input ends with 0 or more digits
• | - or
• ^[a-z] - first character is a letter
• \d\d+ - following characters are 2 or more digits
• $ - end of input

Our regex should match the string JACK
Our regex should not match the string J
Your regex should match the string Jo
Your regex should match the string Oceans11