mgmartel/bp-sort-members-by-last-name.php

## bp-sort-members-by-last-name.php
<?php
// Sort BuddyPress users by last name
//
// Use this Gist to sort members alphabetically by last name in the
// members directory. Follow the instructions below and drop the code
// in your functions.php or your functions plugin.
//
// Updated to work with BP 1.7. See earlier revisions of this gist for
// earlier versions of BP.

/**
 * Sort users by last name
 *
 * Changes the querystring for the member directory to sort users by their last name
 *
 * @param BP_User_Query $bp_user_query
 */
public function alphabetize_by_last_name( $bp_user_query ) {
    if ( 'alphabetical' == $bp_user_query->query_vars['type'] )
        $bp_user_query->uid_clauses['orderby'] = "ORDER BY substring_index(u.display_name, ' ', -1)";
}
add_action ( 'bp_pre_user_query', 'alphabetize_by_last_name' );

// To reflect the alphabetical sorting of the member directory, you
// could also format the names to show the last name first. Here is
// a helper function to format names as follows: Last, First Middle
// Etc.
//
// To use this function every time a user's name is shown or queried,
// simply add it as a filter:
//
// `add_filter ('bp_get_member_name', 'format_last_name_first' );`
//
// To only reformat the name in the member directory, change your
// members/members-loop.php file in your (child)theme. Look for
// `bp_member_name()`
// and replace it with
// `echo format_last_name_first ( bp_get_member_name() );`

/**
 * Helper function for formatting a name: Last, First Middle Etc.
 *
 * @param string $name
 * @return string Formatted name
 */
function format_last_name_first( $name ) {
    if ( $first_space = strrpos( $name, " ") )
        $name = substr( $name, $first_space + 1 ) . ", " . substr( $name, 0, $first_space );
    return $name;
}

// BONUS: To make alphabetical sorting the default sorting, use the
// function below.
//
// In order for this to work properly, `<option value="alphabetical">`
// must be the first option for the members-order-select in
// members/index.php.

function sort_members_alphabetically( $qs = '', $object = false ) {
    if( $object != 'members' ) //for members only
        return $qs;

    if ( empty( $qs ) || ! strpos( $qs, "type=" ) ) {
        $args = wp_parse_args($qs);
        $args['type'] = 'alphabetical';
        $args['action'] = 'alphabetical';

        $qs = build_query( $args );
    }

    return $qs;
}
add_action( 'bp_ajax_querystring', 'sort_members_alphabetically', 11, 2 );
	<?php
	// Sort BuddyPress users by last name
	//
	// Use this Gist to sort members alphabetically by last name in the
	// members directory. Follow the instructions below and drop the code
	// in your functions.php or your functions plugin.
	//
	// Updated to work with BP 1.7. See earlier revisions of this gist for
	// earlier versions of BP.

	/**
	* Sort users by last name
	*
	* Changes the querystring for the member directory to sort users by their last name
	*
	* @param BP_User_Query $bp_user_query
	*/
	public function alphabetize_by_last_name( $bp_user_query ) {
	if ( 'alphabetical' == $bp_user_query->query_vars['type'] )
	$bp_user_query->uid_clauses['orderby'] = "ORDER BY substring_index(u.display_name, ' ', -1)";
	}
	add_action ( 'bp_pre_user_query', 'alphabetize_by_last_name' );

	// To reflect the alphabetical sorting of the member directory, you
	// could also format the names to show the last name first. Here is
	// a helper function to format names as follows: Last, First Middle
	// Etc.
	//
	// To use this function every time a user's name is shown or queried,
	// simply add it as a filter:
	//
	// `add_filter ('bp_get_member_name', 'format_last_name_first' );`
	//
	// To only reformat the name in the member directory, change your
	// members/members-loop.php file in your (child)theme. Look for
	// `bp_member_name()`
	// and replace it with
	// `echo format_last_name_first ( bp_get_member_name() );`

	/**
	* Helper function for formatting a name: Last, First Middle Etc.
	*
	* @param string $name
	* @return string Formatted name
	*/
	function format_last_name_first( $name ) {
	if ( $first_space = strrpos( $name, " ") )
	$name = substr( $name, $first_space + 1 ) . ", " . substr( $name, 0, $first_space );
	return $name;
	}

	// BONUS: To make alphabetical sorting the default sorting, use the
	// function below.
	//
	// In order for this to work properly, `<option value="alphabetical">`
	// must be the first option for the members-order-select in
	// members/index.php.

	function sort_members_alphabetically( $qs = '', $object = false ) {
	if( $object != 'members' ) //for members only
	return $qs;

	if ( empty( $qs ) \|\| ! strpos( $qs, "type=" ) ) {
	$args = wp_parse_args($qs);
	$args['type'] = 'alphabetical';
	$args['action'] = 'alphabetical';

	$qs = build_query( $args );
	}

	return $qs;
	}
	add_action( 'bp_ajax_querystring', 'sort_members_alphabetically', 11, 2 );