WP::build_query_string()

609	public function build_query_string() {610		$this->query_string = '';611 612		foreach ( (array) array_keys( $this->query_vars ) as $wpvar ) {613			if ( '' !== $this->query_vars[ $wpvar ] ) {614				$this->query_string .= ( strlen( $this->query_string ) < 1 ) ? '' : '&';615 616				if ( ! is_scalar( $this->query_vars[ $wpvar ] ) ) { // Discard non-scalars.617					continue;618				}619 620				$this->query_string .= $wpvar . '=' . rawurlencode( $this->query_vars[ $wpvar ] );621			}622		}623 624		if ( has_filter( 'query_string' ) ) {  // Don't bother filtering and parsing if no plugins are hooked in.625			/**626			 * Filters the query string before parsing.627			 *628			 * @since 1.5.0629			 * @deprecated 2.1.0 Use {@see 'query_vars'} or {@see 'request'} filters instead.630			 *631			 * @param string $query_string The query string to modify.632			 */633			$this->query_string = apply_filters_deprecated(634				'query_string',635				array( $this->query_string ),636				'2.1.0',637				'query_vars, request'638			);639 640			parse_str( $this->query_string, $this->query_vars );641		}642	}