If you want .html or other extension files to be treated as php script and parse as .php file, you can do the following.

For web servers using PHP as apache module, add the following line in the .htaccess file.

AddType application/x-httpd-php .html .htm

For web servers running PHP as CGI, add the following line in the .htaccess file.

AddHandler application/x-httpd-php .html .htm 

In the similar way you can mimic by giving asp extension to php file.