A probe into the reasons why PHP files do not write closed tag conventions

When I first started to write PHP code, I was going to write PHP closed tags, and then used to change, no longer write PHP closed tags. This concept was first approached from Drupal and was a bit unaccustomed at first-why not write a closed tag? It's not perfect, it's not suitable for people with obsessive-compulsive disorder. Later, in the work of the problem caused by the closure of the label, it began not to write closed tags.

For a pure php file, the reason for not writing closed tags is to prevent the closure of the label after the extra space, tabs, etc., in the rendering of the page will output these extra characters, resulting in page dislocation; it is also possible that you have a PHP file containing another PHP file, and use the header function, In another PHP file, because there are extra characters behind the enclosing tag, the final page will get an error due to the output before the header function. Therefore, it is highly recommended that you do not write closed tags in pure php files.

This is also mentioned in the Code specification for Zend: http://framework.zend.com/manual/1.12/en/coding-standard.php-file-formatting.html

