echo "hello " world"; # Output hello echo "hello \" world"; # Output hello " world
echo "hello world"; # Output hello world echo "hello \n world"; # Output hello world
\‘ -> ‘
\\ -? \
\"
\n (换行)
\n (tag制表符)
......
$str1 = ‘hello‘; $str2 = ‘world‘; $str = $str1.$str2; echo $str;
原文：https://www.cnblogs.com/burp/p/14400950.html