テーマフォルダの functions.php に以下のようなコードを追加すれば OK◎
<?php
add_action( 'comment_post', 'my_notify_commenters', 10, 2 );
function my_notify_commenters( $comment_id, $comment_approved ) {
$comment = get_comment( $comment_id );
$post = get_post( $comment->comment_post_ID );
global $wpdb;
$email_bcc = $wpdb->get_col( $wpdb->prepare(
"SELECT DISTINCT comment_author_email FROM $wpdb->comments WHERE comment_post_ID = %d AND comment_approved = '1' ORDER BY comment_date",
$post->ID
));
if ( 1 < count( $email_bcc ) ) {
$email_bcc = array_diff( $email_bcc, array( $comment->comment_author_email ) );
$author = $comment->comment_author;
$blogname = wp_specialchars_decode( get_option( 'blogname' ), ENT_QUOTES );
$subject = sprintf( '【%1$s】%2$sが「%3$s」にコメント', $blogname, $author, $post->post_title );
$message = sprintf( '%1$s が「%2$s」にコメントしました。', $author, $post->post_title ) . "\r\n\r\n";
$message .= get_comment_link( $comment_id ) . "\r\n\r\n";
$message .= 'コメント: ' . "\r\n" . strip_tags( $comment->comment_content ) . "\r\n--\r\n";
$headers[] = sprintf( 'From: "%1$s" <%2$s>', $blogname, get_site_option( 'admin_email' ) );
$headers[] = sprintf( 'Bcc: %1$s', implode( ',', $email_bcc ) );
@wp_mail( '', $subject, $message, implode( "\n", $headers ) );
}
}
※会員制ってことで承認関連の処理はイランだろーなと判断して省いてますー