Solving the Problem of PHP Code not Being Executed but Showing in Browser Source Code

If you're experiencing the issue where your PHP code is not being executed but instead shows up as HTML tags in the browser source code, there can be a few possible causes and solutions to this problem. In this article, we will explore these potential issues and provide step-by-step instructions on troubleshooting and resolving the problem.

Cause #1: Incorrect File Extension

First, let's ensure that the file extension of your PHP file is correct. In the problem description, it is mentioned that the file is already named as `filename.php`. However, it's worth double-checking if the file extension is indeed `.php`. The file extension is crucial for Apache to recognize the file as a PHP file and execute the PHP code within it. If the file extension is incorrect or missing, Apache will treat it as a plain HTML file and ignore the PHP code.

Solution #1: Check File Extension

To check the file extension on Windows:


         Right-click on the file and select "Properties".
         In the "General" tab, look for the "Type of file" field.
         Ensure that it shows "PHP File" or "PHP Script". If not, rename the file with the correct extension (.php) and save it.
         

To check the file extension on Mac:


         Right-click on the file and select "Get Info".
         Look for the "Name & Extension" section.
         Ensure that the file name ends with ".php". If not, rename the file with the correct extension and save it.
         

Cause #2: PHP Not Installed or Configured Properly

If the file extension is correct and the PHP code still isn't being executed, the next possible cause could be that PHP is not installed or configured properly on your server. Without a properly configured PHP installation, Apache will not be able to interpret and execute PHP code.

Solution #2: Verify PHP Installation and Configuration

To verify that PHP is installed and configured correctly, follow these steps:

  1. Check if PHP is installed: Open a command prompt or terminal and type the following command: php -v. If PHP is installed, it will display the version information. If not, you need to install PHP.
  2. Check Apache configuration: Open the Apache configuration file (httpd.conf or apache2.conf) and ensure that it contains the following lines:
    
                LoadModule php_module modules/libphp.so (for Linux)
                LoadModule php_module "C:/path/to/php/php7apache2_4.dll" (for Windows)
                
  3. Check PHP.ini configuration: Open the PHP.ini file and ensure that the following lines are uncommented (remove the semicolon if present):
    
                ;extension=php_mysql.dll
                ;extension=php_mysqli.dll
                
  4. Restart Apache: After making any changes to the configuration files, restart the Apache server for the changes to take effect.
  5. Test PHP: Create a simple PHP file with the following code and check if it executes properly:
    
                <?php
                    phpinfo();
                ?>
                
    If the PHP information page is displayed, it means that PHP is installed and configured correctly.

Cause #3: Short Tags Disabled

Another possible cause for PHP code not being executed is the use of short tags (<? ?>) instead of the standard PHP tags (<?php ?>). By default, short tags are disabled on many PHP installations for security reasons. If your PHP code is written using short tags, it won't be executed.

Solution #3: Switch to Standard PHP Tags

To fix this issue, you need to replace all the short tags with standard PHP tags throughout your codebase. Search for occurrences of <? and replace them with <?php.

Cause #4: PHP Code Within HTML Comment Tags

In some cases, PHP code may appear as HTML comments in the source code, preventing it from being executed. If the PHP code is enclosed within HTML comment tags (<!-- -->), it will be treated as a comment and ignored by the PHP interpreter.

Solution #4: Remove PHP Code from HTML Comments

To resolve this issue, search for PHP code enclosed within HTML comment tags and remove the comment tags. For example:


         <!--
             <?php echo "This won't be executed"; ?>
         -->
         

Change it to:


         <?php echo "This will be executed"; ?>
         

Conclusion

By following the steps outlined in this article, you should be able to troubleshoot and resolve the issue of PHP code not being executed but showing up in the browser source code. It's crucial to ensure that the file extension is correct, PHP is installed and configured properly, short tags are not used, and PHP code is not enclosed within HTML comment tags.