Edit single page from plugin

Question

Hello guys I am creating a plugin in which I am making a custom post type season. Now I would like to echo something on season single page based on a database query. I have query and logics figured out but I want to echo on season single page from plugin file only not creating a single template and then use filter like post type template. If you could only show echo 'hello world'; on only post_type="season" that would be great. Thanks.

Answer 1

You could do this with the the_content filter:

/**
 * Adds some text to bottom of the content on 'season' pages.
 *
 * @param   string  $content    The current content of the season page.
 * @return  string              The new content of the season page.
 */
function add_season_content( $content ) {

    if ( is_singular( 'season' ) && is_main_query() ) {

        // collect your season data over here...
        $season_data = 'Hello world';

        $content .= $season_data;
    }

    return $content;

}

add_filter( 'the_content', 'add_season_content' );

Place this code anywhere inside your plugin files.