Check unicode in PHP

Question

How can I check whether a character is a Unicode character or not with PHP?

Answer 1

A unicode character will ALWAYS have the most significant byte set no matter what the value of the character is or if it's part of a multi-byte unicode character or what. You can't just check to see if the string has more bytes than characters since some unicode characters are only one byte. If any character in a string's byte value is greater than 127, that string contains unicode.