Check if String is a Number in PHP using is_numeric() - Pi My Life Up
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SOLVED][2008] Converting an ASCII string to a HEX string-VBForums
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Michael Gillespie on Twitter: "Anyone know how to convert hex (input as a string) to proper UTF-8/char16_t string in PHP? E.g. "4D0061007200E7006F00" == "Março". pack() doesn't seem to do the job. https://t.co/5ewQ6sGMn7" /
Formatting Strings with PHP | Sams Teach Yourself PHP, MySQL and Apache All in One (3rd Edition)
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