Question

On my site, I have a registration page in PHP.
Someone can mimic Ashley by making AshIey.
I do not want this to happen. They replace lowercase L with capital I.
The string is $username and I wanted to check if it contained a capital ‘I’.
If it did, I would set a new string and use an SQL query to see if it existed.
But hat if the username has multiple capital I letters in it? Like DaryII.
I was thinking of doing a foreach statement but didn’t know what to do.
If anyone could give me a little demo of what I need to do, I’d be grateful.

Answer 1

I DID IT!!!

if (preg_match('/[^A-Za-z\d\s]|[^A-Z\s]I|[A-Z]I[a-z]/', $username)) {
die("That username is unavailable for registration.");
}