How to Show PHP Errors in WordPress

If you’re working with WordPress, you’ve probably encountered some pesky PHP errors at some point.

Don’t worry, I’ve got your back! In this article, we’ll learn all about how to tackle those annoying issues and get your site running smoothly again.

We’ll go through everything you need to know about WordPress show PHP errors, so buckle up and let’s dive in!

Understanding PHP Errors

Before we get started, let’s talk about the different types of PHP errors you might come across while working with WordPress.

Familiarizing yourself with these errors will help you troubleshoot more effectively.

Types of PHP errors

• Parse errors: These occur when there’s a syntax issue in your PHP code. They usually point to the exact line where the problem is, making them relatively easy to fix.
• Fatal errors: These are more severe errors that halt the execution of your script. They often occur when you’re trying to call a function or use a class that doesn’t exist.
• Warning errors: Warnings won’t stop your script from running, but they indicate that something is wrong with your code. Ignoring them might lead to more severe issues down the line.
• Notice errors: Notices are the least critical type of error. They’re usually caused by minor issues like using an uninitialized variable, but it’s still a good idea to address them.

Common causes of PHP errors in WordPress

Some of the most common causes of PHP errors in WordPress include:

• Incompatible plugins or themes
• Outdated PHP versions
• Incorrect syntax in custom code
• Errors in core WordPress files

Now that we’ve covered the basics, let’s move on to the fun part: showing and fixing those errors!

The Role of Debugging in WordPress

Debugging is an essential part of working with WordPress. It helps you identify and fix issues in your site’s code, ensuring smooth performance and stability.

The WP_DEBUG constant

WordPress includes a built-in debugging feature called WP_DEBUG. When enabled, it displays PHP errors, warnings, and notices on your site, making it easier for you to identify and resolve issues.

Enabling WP_DEBUG

To enable WP_DEBUG, you’ll need to access and edit your site’s wp-config.php file. Here’s how:

Accessing the wp-config.php file

1. Connect to your website via FTP or cPanel’s File Manager.
2. Locate the wp-config.php file in your site’s root directory.
3. Download a copy of the file as a backup (just in case!).

Editing the wp-config.php file

1. Open the wp-config.php file in a text editor.
2. Locate the line that says /* That's all, stop editing! Happy publishing. */.
3. Just above that line, add the following code: define('WP_DEBUG', true);.
4. Save the file and re-upload it to your site.

With WP_DEBUG enabled, you’ll now see PHP errors, warnings, and notices on your site. Keep in mind that this is great for debugging, but you shouldn’t leave it enabled on a live site. More on that later!

Configuring WP_DEBUG Options

WP_DEBUG has a few additional options you can use to customize your debugging experience. Let’s take a look at them:

WP_DEBUG_LOG

By setting WP_DEBUG_LOG to true, you can save PHP errors to a log file instead of displaying them on your site. Add this line of code to your wp-config.php file: define('WP_DEBUG_LOG', true);.

WP_DEBUG_DISPLAY

If you want to prevent PHP errors from being displayed on your site but still want to log them, you can set WP_DEBUG_DISPLAY to false. Add this line of code to your wp-config.php file: define('WP_DEBUG_DISPLAY', false);.

SCRIPT_DEBUG

Enabling SCRIPT_DEBUG forces WordPress to use the development versions of core CSS and JavaScript files, which can be helpful when debugging. Add this line of code to your wp-config.php file: define('SCRIPT_DEBUG', true);.

SAVEQUERIES

The SAVEQUERIES option helps you analyze the performance of your database queries. When enabled, it saves information about each query executed on your site. Add this line of code to your wp-config.php file: define('SAVEQUERIES', true);.

Enabling PHP Error Reporting via the .htaccess File

Another method to display PHP errors is by modifying your .htaccess file. Here’s how:

Locating the .htaccess file

1. Connect to your website via FTP or cPanel’s File Manager.
2. Find the .htaccess file in your site’s root directory.
3. Download a copy of the file as a backup.

Adding error reporting code

1. Open the .htaccess file in a text editor.
2. Add the following lines of code at the beginning of the file:

3. Save the file and re-upload it to your site.

This method will enable PHP error reporting on your site, allowing you to see and fix any issues that arise.

Using WordPress Plugins for Debugging

There are also several WordPress plugins available that can help you with debugging. These plugins can provide additional functionality and information beyond what WP_DEBUG offers.

Advantages and limitations of using plugins

While using plugins can make debugging easier, they may also introduce new issues, especially if they’re not well-maintained or compatible with your site. Always use caution when installing and using plugins for debugging purposes.

Popular WordPress debugging plugins

• Query Monitor: This plugin provides a wealth of information about your site’s performance, including details about database queries, HTTP requests, and more.
• Debug Bar: Debug Bar adds a toolbar to your site that displays debugging information, such as PHP errors, database queries, and memory usage.
• Log Deprecated Notices: This plugin logs the use of deprecated functions, files, and arguments, helping you identify potential issues in your site’s code.

Debugging WordPress Themes and Plugins

Now that we’ve covered the various debugging tools and techniques, let’s talk about how to debug issues specifically related to themes and plugins.

Identifying problematic themes and plugins

If you suspect that a theme or plugin is causing issues on your site, you can confirm your suspicions by deactivating the theme or plugin and checking to see if the issue persists. If the problem goes away, you’ve found the culprit!

Debugging steps for themes and plugins

1. Check the theme or plugin’s documentation and support forums for known issues and solutions.
2. Look for PHP errors or other issues in the theme or plugin’s code.
3. If you’re unable to resolve the issue, consider reaching out to the theme or plugin’s developer for assistance.

Debugging JavaScript and AJAX in WordPress

JavaScript and AJAX play important roles in the functionality and performance of many WordPress sites. Debugging these elements is essential for ensuring a smooth user experience.

Importance of JavaScript and AJAX debugging

Debugging JavaScript and AJAX can help you identify and resolve issues related to site functionality, performance, and user experience.

Utilizing browser developer tools

Modern web browsers come equipped with developer tools that can help you debug JavaScript and AJAX issues. These tools allow you to view console logs, inspect elements, monitor network activity, and more.

1. Open your browser’s developer tools (usually accessible via F12 or Ctrl+Shift+I on Windows, or Cmd+Option+I on Mac).
2. Check the Console tab for any JavaScript errors or warnings.
3. Inspect the Network tab to monitor AJAX requests and responses.

Using these tools, you can identify and fix issues related to JavaScript and AJAX on your WordPress site.

Troubleshooting Common PHP Error Scenarios

Let’s now discuss how to handle some common PHP error scenarios that you might encounter while working with WordPress.

White screen of death

The infamous “white screen of death” (WSoD) occurs when your site displays a blank white page with no error messages. To troubleshoot the WSoD, try the following steps:

1. Enable WP_DEBUG to display PHP errors.
2. Check your .htaccess file for errors.
3. Disable all plugins and switch to a default theme to identify potential conflicts.

500 internal server error

A 500 internal server error typically indicates a problem with your server or a misconfiguration in your .htaccess file. To resolve this issue, you can:

1. Check your server’s error logs for any clues.
2. Review and correct any issues in your .htaccess file.
3. Increase your site’s PHP memory limit.

Error establishing a database connection

This error occurs when WordPress is unable to connect to your site’s database. To fix it, try the following:

1. Check your wp-config.php file to ensure your database credentials are correct.
2. Verify that your database server is running and accessible.
3. Repair your WordPress database using the built-in repair tool.

Dealing with PHP Errors in a Live Environment

As mentioned earlier, displaying PHP errors on a live site can pose security risks and create a poor user experience. So, how can you debug issues on a live site without exposing sensitive information?

Risks of showing errors on a live site

Displaying PHP errors on a live site can reveal sensitive information, such as file paths and database details, to potential attackers. Additionally, visible errors can undermine your site’s credibility and deter users.

Strategies for debugging in a live environment

1. Use the WP_DEBUG_LOG option to log errors without displaying them on your site.
2. Set up a staging site to replicate and troubleshoot issues in a safe environment.
3. Use browser developer tools to debug JavaScript and AJAX without impacting user experience.

Setting up a Local Development Environment

Setting up a local development environment allows you to work on your WordPress site without affecting the live version. This makes it easier to debug and test changes before deploying them to your live site.

Advantages of local development

• Faster development and testing
• No risk of breaking your live site
• Offline access to your site

Popular local development tools

• Local by Flywheel: A user-friendly local development tool designed specifically for WordPress.
• MAMP: A cross-platform local development solution that supports WordPress, Joomla, Drupal, and more.
• XAMPP: Another popular cross-platform development tool that provides a full web server stack for local development.

By using a local development environment, you can work on and debug your WordPress site with greater confidence and control.

Debugging Performance Issues in WordPress

In addition to PHP errors, performance issues can also negatively impact your WordPress site. Identifying and addressing performance bottlenecks is crucial for maintaining a fast, responsive site.

Identifying performance bottlenecks

Performance bottlenecks can arise from a variety of sources, including inefficient code, slow database queries, and excessive HTTP requests. To identify these issues, you can:

1. Use tools like Google PageSpeed Insights, GTmetrix, or Pingdom to analyze your site’s performance.
2. Monitor your site’s database queries using the SAVEQUERIES option or a plugin like Query Monitor.
3. Inspect your site’s code for inefficient or redundant functions and scripts.

Addressing performance issues

Once you’ve identified performance bottlenecks, you can take steps to address them:

1. Optimize your site’s code, including PHP, JavaScript, and CSS.
2. Utilize caching and content delivery networks (CDNs) to speed up content delivery.
3. Optimize images and other media files to reduce their size and load times.

By addressing performance issues, you can improve your site’s user experience and search engine rankings.

This will enable PHP error reporting on your site, allowing you to see and fix any issues that arise. Just like with WP_DEBUG, remember to only use this method in a development or staging environment.

How can I prevent PHP errors from being displayed on a live site?

To prevent PHP errors from being displayed on a live site while still logging them, you can set WP_DEBUG_DISPLAY to false. Just add define('WP_DEBUG_DISPLAY', false); to your wp-config.php file.

This way, you can keep an eye on errors without exposing them to your users or potential attackers.

Are there any plugins that can help me debug PHP errors?

Yes, there are several WordPress plugins that can help you with debugging PHP errors. Some popular options include Query Monitor, Debug Bar, and Log Deprecated Notices.

These plugins provide additional information and features beyond what the WP_DEBUG feature offers, making debugging easier and more efficient.

How do I troubleshoot PHP errors caused by themes or plugins?

To troubleshoot PHP errors caused by themes or plugins, you can start by deactivating the suspected theme or plugin and checking if the issue persists. If the problem goes away, you’ve found the culprit!

Next, look for any known issues or solutions in the theme or plugin’s documentation and support forums. If you’re still unable to resolve the issue, consider reaching out to the theme or plugin’s developer for assistance.

Can I debug JavaScript and AJAX issues in WordPress?

You bet! Debugging JavaScript and AJAX issues in WordPress is essential for ensuring a smooth user experience. You can use your browser’s built-in developer tools, such as the Console and Network tabs, to monitor JavaScript errors and AJAX requests.

This will help you identify and fix any issues related to these elements without impacting the user experience on your site.

What should I do if I encounter the “white screen of death” or a 500 internal server error?

If you run into the “white screen of death” or a 500 internal server error, don’t panic! These issues can often be resolved by following a few troubleshooting steps:

1. Enable WP_DEBUG to display PHP errors that might be causing the problem.
2. Check your .htaccess file for errors or misconfigurations.
3. Disable all plugins and switch to a default theme to identify potential conflicts.

By systematically working through these steps, you’ll likely be able to identify and fix the issue that’s causing the error.