WordPress Emails

action.php

function set_mail_html_content_type() {
	return 'text/html';
}

add_action( 'publish_post', 'author_publish_notice', 10 ,2 );

function author_publish_notice( $ID, $post ) {
	if( 'post' == $post->post_type ) {
		return;
	}
	$to = 'author@email.com';
	$subject = 'Your Article Is Online';
	$message = '<h1>Congratulations!</h1> <p>Your article is now online and 
		is sure to receives trillions of comments. Please do hang around and answer any questions
		viewers may have!</p> <p><a href="' . get_permalink( $ID ) . '">' . $post->post_title . '</a></p>';
	
	add_filter( 'wp_mail_content_type', 'set_mail_html_content_type' );
	wp_mail( $to, $subject, $message ); 
	remove_filter( 'wp_mail_content_type', 'set_mail_html_content_type' );

}

basic.php

<?php 

$to = 'my@email.com';
$subject = 'Welcome To The Tutorial';
$message = 'Hello! I hope you are enjoying this article, it is great to see you!';

wp_mail( $to, $subject, $message ); 

?>

html.php

function set_mail_html_content_type() {
	return 'text/html';
}

$to = 'my@email.com';
$subject = 'Welcome To The Tutorial';
$message = '<h1>Hello!</h1> <p>I hope you are enjoying this article, it is great to see you!</p>';

add_filter( 'wp_mail_content_type', 'set_mail_html_content_type' );
wp_mail( $to, $subject, $message ); 
remove_filter( 'wp_mail_content_type', 'set_mail_html_content_type' );

simple.php

<?php wp_mail( $to, $subject, $message, $headers, $attachments ); ?>