How to Disable the WordPress Update Notice?

If you want to disable update notification in wordpress than please write below code in functions.php

/*******************  Method 1  ***********************/
//Disable Theme Updates # 3.0+
remove_action( 'load-update-core.php', 'wp_update_themes' );
add_filter( 'pre_site_transient_update_themes', create_function( '$a', "return null;" ) );
wp_clear_scheduled_hook( 'wp_update_themes' );

//Disable Plugin Updates #3.0+
remove_action( 'load-update-core.php', 'wp_update_plugins' );
add_filter( 'pre_site_transient_update_plugins', create_function( '$a', "return null;" ) );
wp_clear_scheduled_hook( 'wp_update_plugins' );

//Diasable Core Updates # 3.0+
add_filter( 'pre_site_transient_update_core', create_function( '$a', "return null;" ) );
wp_clear_scheduled_hook( 'wp_version_check' );


/*******************  Method 2  ***********************/

function remove_core_updates(){

        global $wp_version;
        return (object) array(
            'last_checked' => time(),
            'version_checked' => $wp_version,
            );
}
add_filter('pre_site_transient_update_core', 'remove_core_updates');
add_filter('pre_site_transient_update_plugins', 'remove_core_updates');
add_filter('pre_site_transient_update_themes', 'remove_core_updates');