WordPress, creating magic tags example

wp_magic_tags.php

//get your data with the magic tags
$prefix_old_body = $_POST["field"];

//create the replacement variables
$magic_tag1 = "Data";
$magic_tag2 = "Data2";

//create the list of magic tags you're looking for
$prefix_magic_tags = array( "{magic_tag1}", "{magic_tag2}" );
 
//write your replacement variables in the same order of your magic tags
$prefix_magic_tags_replace = array( $magic_tag1, $magic_tag2 );
 
//get your new replaced data
$prefix_new_body = str_replace( $prefix_magic_tags, $prefix_magic_tags_replace, $prefix_old_body );