stripos returns false when special characters is used

Question

I am using the stripos function to check if a string is located inside another string, ignoring any cases.

Here is the problem:

stripos("ø", "Ø")

returns false. While

stripos("Ø", "Ø")

returns true.

As you might see, it looks like the function does NOT do a case-insensitive search in this case.

The function has the same problems with characters like Ææ and Åå. These are Danish characters.

Answer 1

Use mb_stripos() instead. It's character set aware and will handle multi-byte character sets. stripos() is a holdover from the good old days when there was only ASCII and all chars were only 1 byte.

Answer 2

You need mb_stripos.

Answer 3

mb_stripos will take care of this.

Answer 4

As the other solutions say, try first with mb_stripos(). But if using this function doesn't help, check the encoding of your php file. Convert it to UTF-8 and save it. That did the trick for me after hours of research.