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filter is not described

query_string filter-hook . WP 1.5.0

Deprecated in from version 2.1.0. It is no longer supported and can be removed in future releases. See query_vars.

Deprecated: 2.1.0 Use {@see 'query_vars'} or {@see 'request'} filters instead.

Filters the query string before parsing.

Usage

add_filter( 'query_string', 'filter_function_name_6469', 10, 4 );
function filter_function_name_6469( $query_string, $string, $string, $request ){
	// filter...

	return $query_string;
}
$query_string(string)
The query string to modify.
$string
-
$string
-
$request
-

Changelog

Since 1.5.0 Introduced.
Deprecated Since 2.1.0 Use {@see 'query_vars'} or {@see 'request'} filters instead.

Where the hook is called

WP::build_query_string()
query_string
wp-includes/class-wp.php 554-559
$this->query_string = apply_filters_deprecated(
	'query_string',
	array( $this->query_string ),
	'2.1.0',
	'query_vars, request'
);

Where in WP core the hook is used WordPress

Usage not found.