Checks if a particular user has a role.

WP-check_user_role

#-----------------------------------------------------------------
#	Checks if a particular user has a role.
#	Returns true if a match was found.
#
#	@param string $role Role name.
#	@param int $user_id (Optional) The ID of a user. Defaults to the current user.
#
#	@return bool
#
#-----------------------------------------------------------------
function check_user_role( $role, $user_id = null ) {
 
	if ( is_numeric( $user_id ) )
		$user = get_userdata( $user_id );
	else
		$user = wp_get_current_user();
 
	if ( empty( $user ) )
		return false;
 
	return in_array( $role, (array) $user->roles );
}