In the regular expression, does s include carriage return?

PHPandJAVA {code...} php is null. {code...} java can all be matched. In the document, \ s indicates that blank character carriage return is not a blank character.
The actual test results are different in different environments.

Test File Content
Test.txt
PH
P and JA
VA

$text=file_get_contents('test.txt');#print $text;preg_match("/PH\sP/s",$text,$match);print_r($match);preg_match("/JA\sVA/s",$text,$match);print_r($match);

Php matching is blank

Pattern php =  Pattern.compile("PH\\sP",Pattern.DOTALL);Pattern java =  Pattern.compile("JA\\sVA",Pattern.DOTALL);  BufferedReader  in = new BufferedReader(new FileReader("test.txt"));   StringBuffer  sb=new StringBuffer ();    String s;    while ((s = in.readLine()) != null)     {    sb.append(s); }Matcher m = php.matcher(sb);while(m.find()) {      System.out.println(m.group());}  m = java.matcher(sb);while(m.find()) {      System.out.println(m.group());}

Both java

Reply content:

In this document, \ s indicates that blank characters are not counted as blank characters when you press Enter.
The actual test results are different in different environments.

Test File Content
Test.txt
PH
P and JA
VA

$text=file_get_contents('test.txt');#print $text;preg_match("/PH\sP/s",$text,$match);print_r($match);preg_match("/JA\sVA/s",$text,$match);print_r($match);

Php matching is blank

Pattern php =  Pattern.compile("PH\\sP",Pattern.DOTALL);Pattern java =  Pattern.compile("JA\\sVA",Pattern.DOTALL);  BufferedReader  in = new BufferedReader(new FileReader("test.txt"));   StringBuffer  sb=new StringBuffer ();    String s;    while ((s = in.readLine()) != null)     {    sb.append(s); }Matcher m = php.matcher(sb);while(m.find()) {      System.out.println(m.group());}  m = java.matcher(sb);while(m.find()) {      System.out.println(m.group());}

Both java

Enter/r/n, not blank. It should be included in/s mode,preg_match('/lalla /s',$youString), The dot metacharacter (.) in s Mode matches all characters, including line breaks

If the modifier s is set"Period"Metacharacters match all characters, including line breaks. If this modifier does not exist, the dot does not match the linefeed. This modifier is equivalent to the/s modifier in perl. An anti-character class such as 1 always matches the line break, and does not rely on the settings of the modifier s.

1. A