Fallback function for Advanced Custom Fields plugin for Wordpress

gistfile1.txt

// Fallback if ACF plugin doesn't exist
/**
* Return a custom field stored by the Advanced Custom Fields plugin
*
* @global $post
* @param str $key The key to look for
* @param mixed $id The post ID (int|str, defaults to $post->ID)
* @param mixed $default Value to return if get_field() returns nothing
* @return mixed
* @uses get_field()
*/
function _get_field( $key, $id=false, $default='' ) {
global $post;
$key = trim( filter_var( $key, FILTER_SANITIZE_STRING ) );
$result = '';
if ( function_exists( 'get_field' ) ) {
if ( isset( $post->ID ) && !$id )
$result = get_field( $key );
else
$result = get_field( $key, $id );
if ( $result == '' ) // If ACF enabled but key is undefined, return default
$result = $default;
} else {
$result = $default;
}

return $result;
}

/**
* Shortcut for 'echo _get_field()'
* @param str $key The meta key
* @param mixed $id The post ID (int|str, defaults to $post->ID)
* @param mixed $default Value to return if there's no value for the custom field $key
* @return void
* @uses _get_field()
*/
function _the_field( $key, $id=false, $default='' ) {
echo _get_field( $key, $id, $default );
}

/**
* Get a sub field of a Repeater field
* @param str $key The meta key
* @param mixed $default Value to return if there's no value for the custom field $key
* @return mixed
* @uses get_sub_field()
*/
function _get_sub_field( $key, $default='' ) {
if ( function_exists( 'get_sub_field' ) && get_sub_field( $key ) )
return get_sub_field( $key );
else
return $default;
}

/**
* Shortcut for 'echo _get_sub_field()'
* @param str $key The meta key Value to return if there's no value for the custom field $key
* @return void
* @uses _get_sub_field()
*/
function _the_sub_field( $key, $default='' ) {
echo _get_sub_field( $key, $default );
}

/**
* Check if a given field has a sub field
* @param str $key The meta key
* @param mixed $id The post ID
* @return bool
* @uses has_sub_field()
*/
function _has_sub_field( $key, $id=false ) {
if ( function_exists('has_sub_field') )
return has_sub_field( $key, $id );
else
return false;
}