PHP and WordPress: Debugging

问题:

I am writing some plugins and themes for WordPress, and I finding it hard to debug because somehow by the time the page has loaded, $_GET, $_POST and $_REQUEST are all empty. Even with error reporting set on, I am not getting error messages either other than a blank page whenever there is a fatal error. Is there anyway to enable a 'debug mode' for WordPress?

Thanks!

回答1:

Pear Debug Wordpress plugin: http://wordpress.org/extend/plugins/wp-pear-debug/

Update 4/08/2015: The above plugin hasn't been updated in a few years. You can also use the built-in WordPress PHP debugging functions in wp-config.php , i.e.:

  // Enable WP_DEBUG mode
define('WP_DEBUG', true);

// Enable Debug logging to the /wp-content/debug.log file
define('WP_DEBUG_LOG', true);

// Disable display of errors and warnings 
define('WP_DEBUG_DISPLAY', false);
@ini_set('display_errors',0);

// Use dev versions of core JS and CSS files (only needed if you are modifying these core files)
define('SCRIPT_DEBUG', true);

See https://codex.wordpress.org/Debugging_in_WordPress for the complete docs

回答2:

There's (more than one/) a way to enable "a 'debug mode'" for php in general. And that's installing a debugger extension like e.g. xdebug.
You need a client that connects to the debugger and retrieves+displays the information.
Netbeans 6.7 has been released and its php module supports xdebug. It has become a nice IDE for PHP development.

回答3:

I know this has long been answered, but if you define('WP_DEBUG',true); in your wp-config.php and are still not seeing errors, then add this code right after the define statement:

if (WP_DEBUG) ini_set('display_errors',1);

回答4:

Look at WordPress FirePHP Debugger (spam link removed). It uses FirePHP for debugging wordpress via the web browser.

Main features:

• Automatic detection of FirePHP server library inside php include path or separated directory
• Early loading of the debugger (before WordPress engine starts)
• No modifications to WordPress core or configuration files
• Automatic enabling of WordPress debug mode
• Handles all php fatal errors (no more blank pages and logs parsing)
• Logs WordPress deprecated functions and arguments
• Safe debugging on live site
• SQL queries log
• PHP superglobals and constants
• System information (WordPress and server environment)