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PHP and MySQL
book

PHP and MySQL

by Rheinwerk Publishing, Inc, Christian Wenz, Tobias Hauser
April 2026
Intermediate
1009 pages
34h 15m
English
Packt Publishing
Content preview from PHP and MySQL

7.8    Helpful and Useful Information

This section is the repository for all functions that are too important to be left without an example but do not fit in well with any of the main topics.

7.8.1    ASCII and Conversion

Computers store data as bytes. A byte has a value between 0 and 255. The ASCII character code represents letters and characters within this value range. This means that if a byte has a numerical value, then a numerical code can be used to determine which character matches it. Although ASCII is an old character set, and UTF-8 character sets are now increasingly being used in browsers and HTML documents, you still sometimes need the ASCII code of characters or letters. PHP offers two functions for this:

  • chr(ASCII) converts ...

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Publisher Resources

ISBN: 9781807786373