Line break problem in php

A brief discussion on the problem of line breaks in PHP

1.echo "n"; is just escaped, which is equivalent to a space, but there is no line break, but it is broken in the source file. (Explanation from netizens: n is ASCII code, and the browser parses HTML code, not ASCII code)

2.echo "rn"; After debugging, the result is the same as 1.

3 .echo nl2br("n"); can achieve line breaks. The nl2br() function inserts an HTML newline character (
) before each new line (n) in the string.

Code: echo

Output: line1.

line2

htnl code: line1


line2

4.echo ( "$str");echo ("$str
");echo "";echo "
" The four writing methods can achieve line breaks.

5.
$str="line1nline2";

$str1='line1nlin2';

$str3='lins1rnlin2';

echo $str;

echo $str1;

echo $str2;

echo $str3;

?> line2

line1nlin2

line1rnlin2

line1

line2