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function is not described

_ajax_wp_die_handler() WP 3.4.0

Kills WordPress execution and displays Ajax response with an error message.

This is the handler for wp_die() when processing Ajax requests.

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

No Hooks.

Return

null. Null. Nothing.

Usage

_ajax_wp_die_handler( $message, $title, $args );
$message(string) (required)
Error message.
$title(string)
Error title (unused).
Default: ''
$args(string|array)
Arguments to control behavior.
Default: empty array

Changelog

Since 3.4.0 Introduced.

Code of _ajax_wp_die_handler() WP 5.7

<?php
function _ajax_wp_die_handler( $message, $title = '', $args = array() ) {
	// Set default 'response' to 200 for Ajax requests.
	$args = wp_parse_args(
		$args,
		array( 'response' => 200 )
	);

	list( $message, $title, $parsed_args ) = _wp_die_process_input( $message, $title, $args );

	if ( ! headers_sent() ) {
		// This is intentional. For backward-compatibility, support passing null here.
		if ( null !== $args['response'] ) {
			status_header( $parsed_args['response'] );
		}
		nocache_headers();
	}

	if ( is_scalar( $message ) ) {
		$message = (string) $message;
	} else {
		$message = '0';
	}

	if ( $parsed_args['exit'] ) {
		die( $message );
	}

	echo $message;
}