Replace multiple newlines, tabs, and spaces

Question

I want to replace multiple newline characters with one newline character, and multiple spaces with a single space.

I tried preg_replace(\"/\\n\\n+/\", \"\\n\",

Answer 1

Use \R (which represents any line ending sequence):

$str = preg_replace('#\R+#', '
', $str);

It was found here: Replacing two new lines with paragraph tags

PHP documentation about Escape sequences:

\R (line break: matches \n, \r and \r\n)