我有一个变量,它包含//TheFirstPage(hello.php)$a='goto.php?a_56=63525588000&url=http://www.example.com/site/DISC+cUSTOMc+Studio+24+-+Windows/1142766.p?id=1218224802931&usi=1142766&cmp=RMX&ky=2crslw0k9ZOM0ciu2rqi4NsYY7eQnnEyP';//TheSecondPage(goto.php)$r=$_GET['url'];echo$r;//http://www.example.com/site/Dis