regex for validating folder name & file name

Question

I want to validate a file name

Name of file or folder should not contain \ / ? % * : | " < > .

Could you please suggest me the regex expression to use in preg_match()?

Thanks.

Answer 1

It would be more efficient to use the strpbrk() function.

if (strpbrk($filename, "\\/?%*:|\"<>") === FALSE) {
  /* $filename is legal; doesn't contain illegal character. */
}
else {
  /* $filename contains at least one illegal character. */
}

Answer 2

The regex that meets your requirements: ^[^\\/?%*:|"<>\.]+$