清理空格或回车分隔用于发送引用的URL。

原型

sanitize_trackback_urls( string $to_ping )

参数

$to_ping (string) (Required) 空格或回车符分隔URL

返回值

(string)  以http或https协议开头的URL,以回车符分隔。

源文件

路径:wp-includes/formatting.php

<?php
...
function sanitize_trackback_urls( $to_ping ) {
	$urls_to_ping = preg_split( '/[rnt ]/', trim( $to_ping ), -1, PREG_SPLIT_NO_EMPTY );
	foreach ( $urls_to_ping as $k => $url ) {
		if ( !preg_match( '#^https?://.#i', $url ) )
			unset( $urls_to_ping[$k] );
	}
	$urls_to_ping = array_map( 'esc_url_raw', $urls_to_ping );
	$urls_to_ping = implode( "n", $urls_to_ping );
	/**
	 * Filters a list of trackback URLs following sanitization.
	 *
	 * The string returned here consists of a space or carriage return-delimited list
	 * of trackback URLs.
	 *
	 * @since 3.4.0
	 *
	 * @param string $urls_to_ping Sanitized space or carriage return separated URLs.
	 * @param string $to_ping      Space or carriage return separated URLs before sanitization.
	 */
	return apply_filters( 'sanitize_trackback_urls', $urls_to_ping, $to_ping );
}
...
?>

其他

英文文档:https://developer.wordpress.org/reference/functions/sanitize_trackback_urls/