How to use blog_redirect_404 filter in WordPress

blog_redirect_404 filter

The filter is only evaluated if the NOBLOGREDIRECT constant is defined.

To use the blog_redirect_404 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 modify_blog_redirect_404_defaults which takes 1 parameter and we registered it using add_filter. The first parameter blog_redirect_404 is the name of the hook, the second parameter modify_blog_redirect_404_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 the blog_redirect_404 filter.

Parameters

Below the 1 parameter is required to use this hook.

• $no_blog_redirect: (string) The redirect URL defined in NOBLOGREDIRECT.

Live Example

apply_filters('blog_redirect_404', string $no_blog_redirect)

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

Example 1: Basic Usage

Here’s how you can modify the $no_blog_redirect variable:

    function weplugins_modify_blog_redirect_404_defaults($no_blog_redirect) {
        // Update the $no_blog_redirect variable according to your website requirements and return this variable. You can modify the $no_blog_redirect variable conditionally too if you want.
        return $no_blog_redirect;
    }
    // add the filter
    add_filter("blog_redirect_404", "weplugins_modify_blog_redirect_404_defaults", 10, 1);
    

Example 2: Conditional Modification

Modify the $no_blog_redirect variable conditionally:

    function weplugins_modify_blog_redirect_404_conditionally($no_blog_redirect) {
        if (is_user_logged_in()) {
            $no_blog_redirect = home_url('/dashboard');
        }
        return $no_blog_redirect;
    }
    // add the filter
    add_filter("blog_redirect_404", "weplugins_modify_blog_redirect_404_conditionally", 10, 1);
    

Example 3: Removing the Hook

To remove a hook callback, use the example below:

    remove_filter("blog_redirect_404", "weplugins_modify_blog_redirect_404_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 need any customization or have trouble using this hook, please contact us and we’d be happy to assist you.