下面的代码可以工作，请阅读内联注释。将其粘贴到主题函数中。php或插件。

唯一的问题是，只有在选择模板、保存/更新帖子并且编辑器为空时，它才会起作用。

<?php

function wpse_177576_update_editor_content( $post_id ) {

    if ( wp_is_post_revision( $post_id ) )
        return;

    $post = get_post( $post_id );
    $content = apply_filters( \'the_content\', $post->post_content );

    if ( \'\' != $content )
        return; // content already exists, we don\'t want to overwrite it.

    $template = get_post_meta( $post_id, \'_wp_page_template\', true ); // Returns the template file name i.e. page-accordion.php

    if ( $template == \'page-accordion.php\' ) { // change "page-accordion.php" to the filename of your template
        $content = \'<h1>modify this header for title</h1>
                    <div id="accordion">
                        write you content here
                    </div>\';
    }

    /**
     * Update the post with template content
     */
    wp_update_post( array(
        \'ID\' => $post_id,
        \'post_content\' => $content
    ) );
}
add_action( \'save_post\', \'wpse_177576_update_editor_content\' );