[PHP] Only allowing certain characters in string
I have been looking for a way to create a function to check if a string contains anything other than lower case letters and numbers in it, and if it does return false. I have searched on the internet but all I can find is old methods that require you to use functions that are now deprecated in PHP5.

So how do we do it in PHP5?
[PHP] Only allowing certain characters in string
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I have been looking for a way to create a function to check if a string contains anything other than lower case letters and numbers in it, and if it does return false. I have searched on the internet but all I can find is old methods that require you to use functions that are now deprecated in PHP5.

So how do we do it in PHP5?