由于微博中有字数限制,所以如果你发的是网址,会自动将其变为短网址。之前我的几篇文章介绍了如何将网址转为短网址,这里我们反过来,把短网址还原为实际网址。请参照下面的程序,用PHP实现:
<?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; } ?>
程序运行结果如下:
http://www.bkjia.com/