Regex to block multiple items - php

Question

I have a form on a site that is collecting user details. There was a fool submitting the form with a name like "Barneycok" from different IP addresses, so I learned how to block that name from going through on the form.
I learned a little regex, just enough to write this little piece:
if (preg_match('/\b(\w*arneycok)\b/', $FirstName)){
$error.= "<li><font face=arial><strong>Sorry, an error occured. Please try again later.</strong><br><br>";
$errors=1;
}
The code has worked perfectly and I never got that name coming through anymore. However, recently, someone is entering a string of numbers on the name field.
The string looks like this:
123456789
123498568
123477698
12346897w
If you notice, the first 4 characters are constant throughout.
So how do I add that in my regex above so that if the name starts with "1234", it will simply match that regex and give the user the error code?
Your help will be greatly appreciated.
Jaime

Answer 1

This will match $FirstName which starts with 1234. for matching a specific word like Barneycok you should use this (b|B)arneycok
Regex: ^\s*1234|\b(?:b|B)arneycok\b
1. ^\s*1234 starts with 1234 can contain spaces in starting
2. | is like or condition,
3. \b(?:b|B)arneycok\b matches the word which contains barneycok or Barneycok
Try this code snippet here
if (preg_match('/^1234|\b(?:b|B)arneycok\b/i', $FirstName))
{
$error.= "<li><font face=arial><strong>Sorry, an error occured. Please try again later.</strong><br><br>";
$errors = 1;
}

Answer 2

The following regex will work.
^1234.*

Answer 3

For the sake of providing the best possible pattern to protect your site, I'd like to offer this:
/^\s*1234|barneycok/i
This will match a string that has 1234 as its first non-white characters as well as a string that contains the substring barneycok (case insensitively).
Demo Link
You will notice that the pattern:
omits the leading word boundary (letting it catch abarneycok),
doesn't bother with a non-capturing group with a pipe between B and b (because it is pointless when using the i flag)
omits the trailing word boundary (letting it catch barneycoka)
uses the i flag so that bArNeYcOk is caught.
You can implement the pattern with:
if(preg_match('/^\s*1234|barneycok/i',$FirstName)){
$error.="<li><font face=arial><strong>Sorry, an error occurred. Please try again later.</strong><br><br>";
$errors=1;
}
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