Simple function to enforce whitelist (ensure that a string includes only certain characters) and blacklist (ensure that a string absolutely does not include certain characters).
Want to make sure that a string includes only certain characters? Create a whitelist. Want to make sure that a string absolutely does not include certain characters? Create a blacklist. Both are easy to do with this simple function and structure.
released on 17 August 2007
This entry (in part or in whole) was last reviewed on 6 January 2017.
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