_php tutorial on double quotes and single quotes in PHP

Whether you are writing JavaScript or PHP, you are always accustomed to using single quotes. But the weekend at home coding encounter a problem, you need to filter the string by PHP line breaks, follow the following method:

$out = str_replace (Array (' \ r \ n ', ' \ R ', ' \ n '), ', $out); PHP provides three ways to define strings: single quotes, double quotes, local documents (in English called here Document or Heredoc).

Single quotes:
Using single quotation marks is the most efficient method, because PHP does not check for built-in variables and escape sequences in single-quote strings, only the backslash and the single quotation mark itself that need to be escaped.

Double quotes:
The built-in variables and escape sequences are checked, but escaped single quotes are not recognized. This also illustrates the mistake of starting that code by using double quotation marks to define the escape sequence of the newline:

$out = Str_replace (Array ("\ r \ n", "\ r", "\ n"), "', $out); local Documentation:
Check all built-in variables and escape sequences, with double quotes without escaping. For example:

Echo <<
This is a ' here document ' example.
Just for Test.
EOT; Simply record and deepen the impression.

http://www.bkjia.com/PHPjc/363842.html www.bkjia.com true http://www.bkjia.com/PHPjc/363842.html techarticle Whether you are writing JavaScript or PHP, you are always accustomed to using single quotes. But the weekend at home coding encounter a problem, you need to filter the string through PHP line breaks, according to the following ...

