How to Add Meta Boxes for Custom Post Type in WordPress

This code use for you can add Meta Boses in Custom post Type and this code add your function.php file WordPress.

Custom meta boxes are Mostly used to provide a better user interface for adding custom fields (metadata) into your content.

<?php
function add_service_meta_boxes() {
 add_meta_box("service_contact_meta", "Contact Details", "add_contact_details_service_meta_box", "service", "normal", "low");
}

function add_contact_details_service_meta_box()
{
 global $post;
 $custom = get_post_custom( $post->ID );

 ?>
 <style>.width99 {width:99%;}</style>
 <p>
  <label>Address:</label><br />
  <textarea rows="5" name="address" class="width99"><?= @$custom["address"][0] ?></textarea>
 </p>
 <p>
  <label>Website:</label><br />
  <input type="text" name="website" value="<?= @$custom["website"][0] ?>" class="width99" />
 </p>
 <p>
  <label>Phone:</label><br />
  <input type="text" name="phone" value="<?= @$custom["phone"][0] ?>" class="width99" />
 </p>
 <?php
}


/**
 * Save custom field data when creating/updating posts
 */
function save_service_custom_fields(){
  global $post;

  if ( $post )
  {
    update_post_meta($post->ID, "address", @$_POST["address"]);
    update_post_meta($post->ID, "website", @$_POST["website"]);
    update_post_meta($post->ID, "phone", @$_POST["phone"]);
  }
}
add_action( 'admin_init', 'add_service_meta_boxes' );

add_action( 'save_post', 'save_service_custom_fields' );

?>