Find last occurrence of multple characters

[sys4dm1n]

Let me start by saying, this may sound silly.

I am trying to find the last occurrence of a character which is displayed multiple times throughout a string. Specifically in a file name. I am using str_replace to remove all bad file name characters from the string, however, it also removes the period before the file extension.

I am trying to bring that period back using magic -- or PHP. 😉

$bad_chars = array(" ", ".", ",", ";", ":", "`", "#", "$", "/", "|", "&");
	$user_file = str_replace($bad_chars, "_", $HTTP_POST_FILES['userfile']);

Not sure where to go from here. I could use another instance of str_replace(), however I cannot give a parameter as to where it should start looking for "."

strrpos() won't help me here either. Any suggestions?

[NogDog]

You could use [man]strrpos/man to get the position of the last "." in the string, subtract that from the string length ([man]strlen/man), do your replacing, then use [man]substr_replace/man to put the "." back in, using a negative value of for the offset (from the above calculation).

Or, you could just leave the "." characters in there in the first place, as there is nothing "illegal" about them (except in really old versions of Windows/DOS).