PHP Regular Expression and Apostrophe!

Try

if(preg_match('/^[a-zA-Z/\'/\.-]{2,30}$/',$input)){
     echo 'Hooray!';
}

It throws an error saying that ''' is an invalid modifier.  I am using PHP v5

With my original code it simply denies it as if it were improper input.  

Can you just put your regular expression pattern in double quotes instead of single?

if(preg_match("/^[a-zA-Z\'\.-]{2,30}$/",$input)){
     echo 'Hooray!';
}

I believe you could also, if you want to keep single-quoting in your coding style do something like this (yes, that's three backslashes before the single quote), but I'd recommend my first suggestion (above)...

if(preg_match('/^[a-zA-Z\\\'\.-]{2,30}$/',$input)){
     echo 'Hooray!';
}

Still denies it... Here is my exact code:


function validateName($input){
      #Cannot get apostrophe to work.
      $errorMsg = 'May only consist of (a-z, A-Z, \', ., -, and space)';
      if($input == ''){
            $errorMsg = 'This item is required.';
      } else if(preg_match("/^[a-zA-Z\'\.-]{2,30}$/",$input)){
            $errorMsg = '';
      }
      return $errorMsg;
}

I tried it the second way with the single quotes and 3 slashes and it denied as well.

Can you give us the $input you are passing in?

By the way... it says that you are allowing spaces, but the regular expression pattern doesn't have a space in it (I don't know if experts-exchange is just trimming out that space for some reason).  So if your input has a space in it it will fail the regular expression.

This should have a space in it (before the closing "]"):
"/^[a-zA-Z\'\.- ]{2,30}$/"

Maybe it needs to be quoted:
"/^[a-zA-Z\'\.-\ ]{2,30}$/"

Sorry, just testing it -- I've seen spaces get trimmed out before.

I took the space out, I thought it was causing the problem.  The code above is exact, EE isn't stripping anything.

The input is these three names.  The function is called from a loop.

O'Dell
O'Brian
O'Brian-Mc.Donald (What an unfortunate married name eh?)

I think I found the problem...  I don't know what it is, but I found it :)

My loop isn't in the same file.  Its submitting it through a form...  So its actually coming in as post data.  If I take the regexp and put it in a new .php file and run it it works fine.  When I do it through the form it fails.  Magic quotes are turned off and I am not adding slashes (at this time).

Glad you fixed it!  So if I understand correctly you are passing those last names (with quotes, etc...) through a form and then checking them against a regular expression?

To further help with this I would try printing out each name before you check the regular expression to see how the form is handling those special characters.

Well, I didn't fix it...  I found the problem :)
Your regex works great, but it fails when passed through a form!?!

Yes, so you are passing "O'Brian-Mc.Donald" through a form and reading it like $_POST["lastname"].

Before you check the regular expression try printing out the value and let us know what it is (so that we can see what is happening to the form value when it comes through).  Then we'll be able to help you fix it.

Web Host had magic quotes on after all.  All fixed! :)

Great!  Yeah it sure looked like you were getting some garbled post data.  Glad things are working!