听起来你的配置好像有问题，下面是一些你可以检查的东西:

Make sure that PHP is installed and running correctly. This may sound silly, but you never know. An easy way to check is to run php -v from a command line and see if returns version information or any errors. Make sure that the PHP module is listed and uncommented inside of your Apache's httpd.conf This should be something like LoadModule php5_module "c:/php/php5apache2_2.dll" in the file. Search for LoadModule php, and make sure that there is no comment (;) in front of it. Make sure that Apache's httpd.conf file has the PHP MIME type in it. This should be something like AddType application/x-httpd-php .php. This tells Apache to run .php files as PHP. Search for AddType, and then make sure there is an entry for PHP, and that it is uncommented. Make sure your file has the .php extension on it, or whichever extension specified in the MIME definition in point #3, otherwise it will not be executed as PHP. Make sure you are not using short tags in the PHP file (<?), these are not enabled on all servers by default and their use is discouraged. Use <?php instead (or enable short tags in your php.ini with short_open_tag=On if you have code that relies on them). Make sure you are accessing your file over your webserver using an URL like http://localhost/file.php not via local file access file://localhost/www/file.php

最后，查看PHP手册以获得更多的设置技巧。

确保脚本包含

<?php

在应该执行的代码之前。<?之间不能有空格这里是PHP。

这是我的。htaccess

DirectoryIndex index.html index.htm

index.html包含PHP代码。默认情况下，PHP不会将扩展名为htm*的文件作为PHP代码处理。

你可以通过在.htaccess中添加以下内容来覆盖它:

<FilesMatch ".+\.html$">
    SetHandler application/x-httpd-php
</FilesMatch>

此问题的另一个可能原因可能是您试图在UserDir模块的“用户目录”中运行脚本。在用户目录下运行PHP脚本默认是禁用的。如果脚本位于主文件夹的public_html目录中，并且您试图从http://localhost/~your_username访问它，那么就会遇到这个问题。

要解决这个问题，打开/etc/apache2/mods-enabled/php7.2.conf。必须注释或删除底部的标记块

<IfModule mod_userdir.c>
    <Directory /home/*/public_html>
        php_admin_flag engine Off
    </Directory>
</IfModule>

我发布这个答案是因为我的Virtualmin/Webmin管理界面决定禁用我的PHP引擎是一个好主意。我花了一段时间才找到解决方案，所以我想和你们分享一下:

同时，确保你的网站配置文件中没有任何与这个特定主机或虚拟主机相关的php_admin_value在它们中关闭PHP，就像这样:

php_admin_value engine Off

有疑问的时候，评论一下…

# php_admin_value engine Off

并重新启动您的web服务器。

php7:

sudo a2enmod proxy_fcgi setenvif
sudo a2enconf php7.0-fpm
sudo service apache2 restart