I am fairly new to PHP but need to write some validation scripts for eForm to limit certain characters. But even further I would like to rather than black list characters I would rather write strict validation that would white list only certain input.
What would the actual line of code be and where should I place it:
To only permit letters (caps and lower) a-z
To only permit letters (caps and lower) and numbers
To only permit numbers and "-" (dash) symbol
To only permit letters, numbers, quotes, commas, periods and question marks; and strip any html to basic text
Should this be an input by input item item or perhaps in a snipet?
