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How to replace different newline styles in PHP the smartest way?

Asked 2011-10-20T13:26:20.430
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I have a text which might have different newline styles. I want to replace all newlines '\r\n', '\n','\r' with the same newline (in this case \r\n ).

What's the fastest way to do this? My current solution looks like this which is way sucky:

    $sNicetext = str_replace("\r\n",'%%%%somthing%%%%', $sNicetext);
    $sNicetext = str_replace(array("\r","\n"),array("\r\n","\r\n"), $sNicetext);
    $sNicetext = str_replace('%%%%somthing%%%%',"\r\n", $sNicetext);

Problem is that you can't do this with one replace because the \r\n will be duplicated to \r\n\r\n .

Thank you for your help!

php replace newline unify
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$string = preg_replace('~\R~u', "\r\n", $string);

If you don't want to replace all Unicode newlines but only CRLF style ones, use:

$string = preg_replace('~(*BSR_ANYCRLF)\R~', "\r\n", $string);

\R matches these newlines, u is a modifier to treat the input string as UTF-8.

From the PCRE docs:

What \R matches

By default, the sequence \R in a pattern matches any Unicode newline sequence, whatever has been selected as the line ending sequence. If you specify

     --enable-bsr-anycrlf

the default is changed so that \R matches only CR, LF, or CRLF. Whatever is selected when PCRE is built can be overridden when the library functions are called.

and

Newline sequences

Outside a character class, by default, the escape sequence \R matches any Unicode newline sequence. In non-UTF-8 mode \R is equivalent to the following:

    (?>\r\n|\n|\x0b|\f|\r|\x85)

This is an example of an "atomic group", details of which are given below. This particular group matches either the two-character sequence CR followed by LF, or one of the single characters LF (linefeed, U+000A), VT (vertical tab, U+000B), FF (formfeed, U+000C), CR (carriage return, U+000D), or NEL (next line, U+0085). The two-character sequence is treated as a single unit that cannot be split.

In UTF-8 mode, two additional characters whose codepoints are greater than 255 are added: LS (line separator, U+2028) and PS (paragraph separator, U+2029). Unicode character property support is not needed for these characters to be recogniz

answered 2011-10-20T13:31:10.690

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