How to use allow_subdirectory_install filter in WordPress

allow_subdirectory_install filter

Filters whether to enable the *subdirectory installation* feature in Multisite.

To use `allow_subdirectory_install` filter, first you have to register it using `add_filter`. You can write this code into `functions.php` of your activated theme or in a custom WordPress Plugin.

We at WePlugins always prefer to create a custom WordPress Plugin while using hooks so nothing breaks when you update your WordPress Theme in the future.

In the below live example, we have defined a function `weplugins_modify_allow_subdirectory_install_defaults` which takes 1 parameter and we registered using `add_filter`. The first parameter `allow_subdirectory_install` is the name of the hook, the second parameter `weplugins_modify_allow_subdirectory_install_defaults` is the name of the function which needs to be called, the third parameter is the priority of calling the hook if the same hook is used multiple times, and the last parameter is the number of arguments (if any) to be passed in the registered function.

Sometimes, you have to remove a registered hook so you can use `remove_filter` to remove `allow_subdirectory_install` filter.

Parameters

Below the 1 parameter is required to use this hook.

• $allow : (bool) Whether to enable the *subdirectory installation* feature in Multisite. Default false.

Live Examples

Example 1: Basic Usage

Below is an example of how you can use this hook.

    function weplugins_modify_allow_subdirectory_install_defaults($allow) { 
        // Update the $allow variable according to your website requirements and return this variable. You can modify the $allow variable conditionally too if you want.
        return $allow; 
    }
    // add the filter
    add_filter("allow_subdirectory_install", "weplugins_modify_allow_subdirectory_install_defaults", 10, 1);
    

Example 2: Conditional Usage

In this example, the subdirectory installation feature is enabled only if the site is not in a production environment.

    function weplugins_conditional_allow_subdirectory_install($allow) { 
        if (defined('WP_ENV') && WP_ENV !== 'production') {
            $allow = true; // Enable subdirectory install for non-production environments
        }
        return $allow; 
    }
    // add the filter
    add_filter("allow_subdirectory_install", "weplugins_conditional_allow_subdirectory_install", 10, 1);
    

Example 3: Removing the Hook

To remove a hook callback, use the example below.

    remove_filter("allow_subdirectory_install", "weplugins_modify_allow_subdirectory_install_defaults", 10, 1);
    

Please make sure to provide the same callback function name, priority, and number of arguments while removing the hook callback.

Contact Us

If you’re having any trouble using this hook or need customization, please contact our team and we’d be happy to assist you.