PHP restores Weibo short address to actual URL_PHP tutorial

Due to the character limit in Weibo, if you post a URL, it will automatically be converted into a short URL. Several of my previous articles introduced how to convert a URL to a short URL. Here we go the other way and restore the short URL to the actual URL. Please refer to the following program to implement it with PHP:

<?php
$url = "http://163.fm/1QLJ8U";
echo unshorten($url);
function unshorten($url) 
{
	$url = trim($url);
	$headers = get_headers($url);
  	$location = $url;
  	$short = false;
  	foreach($headers as $head) 
	{
    	if($head=="HTTP/1.1 302 Found") 
			$short = true;
    	if($short && startwith($head,"Location: ")) 
		{
      		$location = substr($head,10);
    	}
  	}
  	return $location;
}
function startwith($Haystack, $Needle)
{
	return strpos($Haystack, $Needle) === 0;
}
?>

The results of running the program are as follows:

http://www.bkjia.com/

http://www.bkjia.com/PHPjc/752386.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/752386.htmlTechArticleDue to the character limit in Weibo, if you post a URL, it will automatically be changed into a short URL . Several of my previous articles introduced how to convert URLs to short URLs, here we go the other way...