check-user-roles-function.php

<?php

/**
 * Checks if a particular user has one or more roles.
 *
 * Returns true on first matching role. Returns false if no roles match.
 *
 * @param array|string $roles   - Role name (or array of names).
 * @param int          $user_id - (Optional) The ID of a user. Defaults to the current user.
 * 
 * @uses get_userdata()
 * @uses wp_get_current_user()
 * 
 * @return bool
 */
function check_user_roles( $roles, $user_id = null ) {
    // Default user ID.
    $user = wp_get_current_user();

    // Set user ID.
    if ( is_numeric( $user_id ) ) {
        $user = get_userdata( $user_id );
    }
    // Bail early?
    if ( empty( $user ) ) {
        return false;
    }
    // Get user roles.
    $user_roles = (array) $user->roles;
    // Loop through user roles.
    foreach ( (array) $roles as $role ) {
        if ( in_array( $role, $user_roles ) ) {
            // Role found.
            return true;
        }
    }
    // Role(s) not found.
    return false;
}