php 获取网址参数

echo "rewrite: ".$_GET["rewrite"];  
echo "<br>SERVER_PORT: ".$_SERVER["SERVER_PORT"];  
echo "<br>HTTP_HOST: ".$_SERVER["HTTP_HOST"];  
echo "<br>SERVER_NAME: ".$_SERVER["SERVER_NAME"];  
echo "<br>REQUEST_URI: ".$_SERVER["REQUEST_URI"];  
echo "<br>PHP_SELF: ".$_SERVER["PHP_SELF"];  
echo "<br>QUERY_STRING: ".$_SERVER["QUERY_STRING"];  
echo "<br>HTTP_REFERER: ".$_SERVER["HTTP_REFERER"];