How to alter or add custom url links in simple sitemap in drupal 8?

 It is very simple method, we have 2 options in Drupal 8.

https://www.drupal.org/project/simple_sitemap

1. we can add by config page of module like (//localhost//admin/config/search/simplesitemap/custom). There add custom links with priority with change frequency.

2. we can use alter method with simple steps::

a. Create any custom module or write code in any existing custom module.

b. go to custom_module.module file or create new if not exist.

c. write code line with below given example:

Example:

First render class library in file header.

use Drupal\simple_sitemap\Simplesitemap;

/**

 * Use this hook to add arbitrary links to the sitemap.

 *

 * @param array &$arbitrary_links

 */

function finder_simple_sitemap_arbitrary_links_alter(&$arbitrary_links) {

  // Add an arbitrary link.

  $arbitrary_links = array([

    'url' => 'https://localhost/applications',

    'priority' => '0.9',

    'lastmod' => '2020-05-25T14:40:30+02:00',

    'changefreq' => 'daily',

],

[

'url' => 'https://localhost/products',

    'priority' => '0.7',

    'lastmod' => '2020-07-15T13:40:30+02:00',

    'changefreq' => 'daily',

    ],

);

}

Note: We can't add date(lastmod) in custom links by admin, so we have to use alter code for add dates(lastmod) in custom create links.

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