Mainly in two places:
1. httpd.conf
LoadModule php5_module "D:/app/php/php5apache2_4.dll"
AddHandler application/x-httpd-php .php
PHPIniDir "D:/app/php"
AddType application/x-httpd-php .php
2. php.ini
load module
extension_dir = "D:/app/php/ext"
debugging:
[Xdebug]
zend_extension="D:/app/php/ext/php_xdebug-2.3.2-5.6-vc11-x86_64.dll"
xdebug.auto_trace = On
xdebug.show_exception_trace = On
xdebug.remote_autostart = On
xdebug.remote_enable = On
xdebug.collect_vars = On
xdebug.collect_return = On
xdebug.collect_params = On