Uninstall script for a plugin in Multisite

Question

I've just realized that the traditional uninstall.php file along a plugin is not working in Multisite.

if ( !defined( 'WP_UNINSTALL_PLUGIN' ) ) 
    exit();

delete_option( 'plugin_option_name' );

This doesn't delete the sub-sites options in all wp_SITE-ID_options tables.

Is there a standard way for doing this?

Answer 1

Searching inside all uninstall.php files that I have in my hard-drive, I've found two that had the function is_multisite(): User Role Editor and Add Code to Head.

Both use a $wpdb loop. Simplified:

<?php
/**
 * Plugin Uninstall Procedure
 */

// Make sure that we are uninstalling
if ( !defined( 'WP_UNINSTALL_PLUGIN' ) ) 
    exit();

// Leave no trail
$option_name = 'plugin_option_name';

if ( !is_multisite() ) 
{
    delete_option( $option_name );
} 
else 
{
    global $wpdb;
    $blog_ids = $wpdb->get_col( "SELECT blog_id FROM $wpdb->blogs" );
    $original_blog_id = get_current_blog_id();

    foreach ( $blog_ids as $blog_id ) 
    {
        switch_to_blog( $blog_id );
        delete_option( $option_name );     

        // OR
        // delete_site_option( $option_name );  
    }

    switch_to_blog( $original_blog_id );
}

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